The Difference Between Flysky AFHDS3 Receivers

Nov 17, 2024

0 comments

AFHDS3 Receiver FGr4B FGr4D FGr4P FGr4S Flysky RC Boat RC Car RC Receiver Receiver Comparison

Flysky FGr4D FGr4B FGr4S FGr4P AFHDS3 receiver comparison | SoarSky

Home / Technology Sharing / The Difference Between Flysky AFHDS3 Receivers

Last Updated: August 2026 | Reading Time: 10 minutes | Difficulty: Beginner | Author: Dannyi Chen

Dannyi Chen — RC Enthusiast & Technical Writer at SoarSky. Specializes in Flysky radio systems and AFHDS3 receiver setups for RC cars and boats.

⚡ Quick Answer

Flysky offers four 4-channel AFHDS3 receivers: the enhanced FGr4D (dual built-in antennas, PPX6, 3.5–9V DC input, $37.99) and FGr4B (lightest at 6.4g, external antenna, PPX6, 3.5–9V, $35.99), plus the classic FGr4S (built-in single antenna, PPX4, 3.5–8.4V, $29.99) and FGr4P (150mm single antenna, PPX4, 3.5–8.4V, $28.99). Choose the FGr4D for on-road racing and boats, the FGr4B for weight-sensitive off-road builds, and the FGr4S or FGr4P for reliable budget-friendly performance. All four support PWM/PPM/i.BUS/S.BUS output and bind with any AFHDS3 transmitter. (Source: Flysky official specifications)

I. What Are the Flysky AFHDS3 Receivers Compared in This Guide?
II. How Do the Four AFHDS3 Receivers Compare on Specifications?
III. Which AFHDS3 Receiver Has the Best Size, Weight, and Design?
IV. What Input Power Range Does Each Receiver Support?
V. How Do Binding Mode and Antenna Design Differ?
VI. Which AFHDS3 Receiver Is the Most Waterproof?
VII. Which AFHDS3 Receiver Should You Choose for Your RC Model?
VIII. What Do RC Drivers Say About These Receivers?
IX. Frequently Asked Questions
X. Where to Buy Flysky AFHDS3 Receivers

What Are the Flysky AFHDS3 Receivers Compared in This Guide?

This guide compares Flysky's four 4-channel AFHDS3 receivers — FGr4D, FGr4B, FGr4S, and FGr4P — covering their design, power handling, antennas, waterproofing, and ideal applications. When it comes to remote-controlled (RC) vehicles and boats, the receiver plays a crucial role in translating the signals from the transmitter into precise control actions. Flysky, a well-known brand in the RC community, built the AFHDS3 (third-generation Automatic Frequency Hopping Digital System) protocol to deliver faster response, stronger anti-interference performance, and two-way telemetry on its modern radios such as the Noble NB4 and PL18 series.

All four receivers in this comparison speak the same AFHDS3 language and offer 4 PWM channels, but they differ meaningfully in hardware: the FGr4D and FGr4B are enhanced models with upgraded power handling and higher waterproof ratings, while the FGr4S and FGr4P are classic models that keep costs low without sacrificing core reliability. Understanding these differences helps you match the right receiver to your chassis, your power system, and your budget.

Flysky FGr4D AFHDS3 enhanced receiver with dual built-in antennas | SoarSky

The Flysky FGr4D — the flagship enhanced AFHDS3 receiver in this comparison — available at SoarSky

How Do the Four AFHDS3 Receivers Compare on Specifications?

The FGr4D and FGr4B lead on power range (3.5–9V), waterproofing (PPX6), and binding convenience (button), while the FGr4S and FGr4P match them on channels and data output at a lower price. The table below puts every key specification side by side so you can spot the differences at a glance.

Specification	✦ FGr4D	FGr4B	FGr4S	FGr4P
Type	Enhanced	Enhanced	Classic	Classic
Dimensions	30.3 × 25.8 × 20mm	17 × 29 × 16mm	25.5 × 22 × 17.3mm	29 × 22 × 16.2mm
Weight	7.2g	6.4g	5.1g	8g
Input Power	3.5–9V DC	3.5–9V DC	3.5–8.4V DC	3.5–8.4V DC
PWM Channels	4	4	4	4
BVD (Battery Voltage Detection)	Supported	Supported	—	—
Binding Mode	Button	Button	Binding cable	Binding cable
Antenna	Dual built-in antennas	External single antenna	Built-in single antenna	Single antenna (150mm)
Waterproof Rating	PPX6	PPX6	PPX4	PPX4
Data Output	PWM / PPM / i.BUS / S.BUS/i.BUS 2	PWM / PPM / i.BUS / S.BUS/i.BUS 2/ PPM	PWM / PPM / i.BUS / S.BUS/i.BUS 2	PWM / PPM / i.BUS / S.BUS/i.BUS 2/ PPM
Compatible Transmitters	AFHDS3 transmitters	AFHDS3 transmitters	AFHDS3 transmitters	AFHDS3 transmitters
Recommended Models	On-road racing, 1/10 touring car, 1/10 IC, 1/8 IC boat	Off-road racing, 1/8 & 1/10 buggy, 1/8 & 1/10 truggy, boat	On-road racing, 1/10 touring car, 1/10 IC, 1/8 IC	Off-road racing, 1/8 & 1/10 buggy, 1/8 & 1/10 truggy
Price at SoarSky	$37.99	$35.99	$29.99	$28.99

Source: Flysky official specifications. Prices checked against the SoarSky store in August 2026.

Which AFHDS3 Receiver Has the Best Size, Weight, and Design?

The FGr4B offers the most compact footprint (17 × 29 × 16mm), the FGr4S is the lightest at 5.1g, and the FGr4D is the largest of the four at 30.3 × 25.8 × 20mm and 7.2g — a trade-off that buys you dual built-in antennas. Size and weight matter more than most drivers expect: in a tight 1/10 touring car receiver box or a small boat hull, a few millimeters decide whether the receiver sits flat or has to be shoehorned in.

Enhanced models: FGr4D and FGr4B

The enhanced pair adds upgraded circuitry, a wider input voltage range, and PPX6-level water protection. The FGr4D houses dual built-in antennas in a slightly taller shell, so there is no antenna wire to route or break — ideal for clean installations. The FGr4B keeps a slim, low-profile body with one external antenna you can position for optimal reception.

Flysky FGr4D enhanced AFHDS3 receiver compact design | SoarSky

FGr4D's all-in-one shell eliminates exposed antenna wires — available at SoarSky

Flysky FGr4B AFHDS3 enhanced receiver with external antenna | SoarSky

The FGr4B is the smallest enhanced receiver in the AFHDS3 lineup — available at SoarSky

Classic models: FGr4S and FGr4P

The classic pair shares the same proven AFHDS3 core at a friendlier price. The FGr4S hides its single antenna inside the case for maximum convenience, while the FGr4P uses a 150mm external antenna that can be routed away from noise sources such as ESCs and motors — useful in larger off-road chassis.

Flysky FGr4S V2 AFHDS3 classic receiver built-in antenna | SoarSky

The FGr4S V2 — a compact classic receiver with a built-in antenna — available at SoarSky

What Input Power Range Does Each Receiver Support?

The enhanced FGr4D and FGr4B accept 3.5–9V DC, while the classic FGr4S and FGr4P accept 3.5–8.4V DC (Source: Flysky official specifications). That extra headroom matters if you run your receiver straight off a 2S LiPo: a fully charged 2S pack sits at 8.4V, which is exactly the ceiling of the classic models and leaves no safety margin, whereas the enhanced receivers tolerate the voltage spikes that high-voltage BECs and direct-battery setups can produce.

⚠️ Important: If you power the receiver directly from a 2S LiPo or a high-voltage BEC, choose the FGr4D or FGr4B. Running a classic FGr4S/FGr4P above 8.4V risks permanent damage.

How Do Binding Mode and Antenna Design Differ?

The FGr4D and FGr4B bind with a simple onboard button, while the FGr4S and FGr4P require the included binding cable — and each receiver takes a different approach to antenna placement. These two details define the day-to-day ownership experience more than any other specification.

Binding mode

Button binding on the enhanced models means you can re-bind at the track in seconds with no extra parts to lose. Cable binding on the classic models is just as reliable, but you need to keep the small binding plug in your tool bag — misplace it, and re-binding waits until you get home.

Antenna options

The FGr4D's dual built-in antennas provide the best signal diversity with zero exposed wire — the strongest choice for crowded race environments. The FGr4B's external single antenna can be positioned for optimal reception in tight installs. The FGr4S's built-in single antenna keeps everything inside the case, and the FGr4P's 150mm single antenna gives you the most routing flexibility in large off-road vehicles.

💡 Tip: Whichever receiver you choose, keep antenna wires away from carbon fiber, ESC power leads, and motor wires to minimize interference.

Which AFHDS3 Receiver Is the Most Waterproof?

The FGr4D and FGr4B carry the highest waterproof rating in the lineup at PPX6 (marked PPX6 on the housing), protecting against powerful water jets, while the FGr4S and FGr4P are rated PPX4 (PPX4) for splash resistance (Source: Flysky official specifications). For RC boats, rainy-day bashing, and wet grass running, the enhanced receivers' PPX6 sealing is a genuine advantage — it protects the internals from the water exposure that kills unprotected electronics. The classic models still shrug off splashes and light rain, but they should not see direct jets or submersion.

Flysky FGr4P AFHDS3 classic receiver 150mm antenna | SoarSky

The FGr4P with its 150mm antenna — a flexible budget option for off-road builds — available at SoarSky

Which AFHDS3 Receiver Should You Choose for Your RC Model?

Choose the FGr4D for on-road racing and boats, the FGr4B for off-road buggies and truggies where weight matters, the FGr4S for budget on-road builds, and the FGr4P for budget off-road builds — every option delivers the same reliable AFHDS3 link. Match the receiver to your scenario with the guide below.

FGr4D — best overall for on-road racing and boats

The FGr4D combines dual built-in antennas, PPX6 waterproofing, 3.5–9V input, BVD battery voltage detection, and button binding. It is the worry-free choice for 1/10 touring cars, 1/10 and 1/8 IC on-road cars, and RC boats, where signal stability and water protection are non-negotiable.

FGr4B — best for weight-sensitive off-road builds

The FGr4B packs the same enhanced electronics into the smallest shell in the lineup (6.4g, 17 × 29 × 16mm). Its external antenna routes easily in 1/8 and 1/10 buggies and truggies, and the PPX6 rating survives mud and wet tracks. Flysky also recommends it for boats.

FGr4S — best budget option for on-road

The FGr4S is the lightest receiver here (5.1g) with a fully internal antenna and the classic 3.5–8.4V input range. For club-level 1/10 touring and IC on-road cars powered through a standard ESC BEC, it delivers full AFHDS3 performance at the lowest weight and a lower price than the enhanced models.

FGr4P — best budget option for off-road

The FGr4P's 150mm external antenna reaches up and out of crowded electronics bays in 1/8 and 1/10 buggies and truggies. It is the most affordable receiver in this comparison and a smart spare to keep in the pit bag.

✅ Verdict: Buy the FGr4D if you want maximum signal security and waterproofing, the FGr4B if every gram counts, and the FGr4S or FGr4P if you want proven AFHDS3 performance on a budget.

FlySky 4CH Bidirectional RX FGR4D

$37.99

🛒 Buy Now

Flysky FGr4B 2.4GHz 4-Channels enhanced receiver

$35.99

🛒 Buy Now

SoarskyRC Flysky FGr4S V2 Receiver, 2.4GHz 4CH AFHDS 3 Receiver

$29.99

🛒 Buy Now

FlySky FGR4P 2.4GHz 4CH AFHDS3 RC Receiver

$28.99

🛒 Buy Now

What Do RC Drivers Say About These Receivers?

Here is verified buyer feedback from SoarSky customers, supplemented by the SoarSky editorial team's hands-on experience with the full AFHDS3 receiver lineup.

✅ Verified Judge.me buyer review

Carl Woodruff — March 2025 ★★★★★ Verified Purchase

"Works as it was designed to." — FGr4S V2

🔬 SoarSky Editorial Team Hands-On Experience

FGr4D — Editorial Test

We installed the FGr4D in a 1/10 touring car paired with the Noble NB4. Button binding completed in under 10 seconds with no binding cable required. The dual built-in antennas eliminated the need for antenna tube routing entirely. Signal remained stable across a full race day with no glitches or dropouts. The PPX6 rating held up during a wet-track session — internals stayed dry.

FGr4B — Editorial Test

The FGr4B was fitted into a 1/10 off-road buggy where receiver bay space is tight. At 6.4g and 17 × 29 × 16mm, it sat flat in the receiver box with room to spare. We powered it directly from a 2S LiPo (8.4V fully charged) — the 9V ceiling provided the safety margin the classic models lack. The external antenna was routed up the body post without any signal issues over a full afternoon of bashing.

FGr4P — Editorial Test

The FGr4P was tested in a 1/8 truggy with a crowded electronics bay. The 150mm antenna routed cleanly up the body post and away from the ESC and motor leads. Binding required the included cable — keep it in your pit bag. Performance was indistinguishable from the enhanced models at normal racing distances. At $28.99, it is the most cost-effective way to add a spare receiver to the pit box.

💡 What we found: All four receivers deliver the same reliable AFHDS3 link. The FGr4D and FGr4B stand out for button binding, PPX6 waterproofing, and 9V input tolerance — worth the small price premium for racing and boat use. The FGr4S and FGr4P are solid budget choices for standard ESC BEC setups.

Frequently Asked Questions

What is the difference between Flysky FGr4D and FGr4B?

Both are enhanced AFHDS3 receivers with 3.5–9V input, PPX6 waterproofing, button binding, and BVD, but the FGr4D uses dual built-in antennas in a taller shell (7.2g), while the FGr4B is smaller and lighter (6.4g, 17 × 29 × 16mm) with a single external antenna. Choose the FGr4D for maximum signal diversity in on-road cars and boats; choose the FGr4B when space and weight are tight in off-road builds.

Are these AFHDS3 receivers compatible with AFHDS 2A transmitters?

No. The FGr4D, FGr4B, FGr4S, and FGr4P only work with AFHDS3 transmitters such as the Flysky Noble NB4 series and PL18 series. They cannot bind to older AFHDS or AFHDS 2A radios, so make sure your transmitter supports the AFHDS3 protocol before ordering.

Can I power these receivers directly from a 2S LiPo battery?

Only the enhanced FGr4D and FGr4B are safe for direct 2S LiPo power, thanks to their 3.5–9V input range. The classic FGr4S and FGr4P top out at 8.4V — exactly the full-charge voltage of a 2S pack — so they should be powered through a regulated ESC BEC instead.

Which AFHDS3 receiver is best for RC boats?

The FGr4D is the best AFHDS3 receiver for RC boats because it combines PPX6 waterproofing with dual built-in antennas that keep a stable link across open water. Flysky also recommends the FGr4B for boats, making the enhanced pair the safest choices for wet environments.

Do all four receivers support S.BUS and i.BUS output?

Yes. All four AFHDS3 receivers — FGr4D, FGr4B, FGr4S, and FGr4P — support PWM, PPM, i.BUS, and S.BUS data output, so they integrate with standard servos and ESCs as well as flight controllers and other single-wire devices.

What is BVD on Flysky receivers and which models have it?

BVD (Battery Voltage Detection) is a telemetry function that reports your model's battery voltage back to the transmitter so you can monitor it in real time. On this lineup, BVD is supported by the enhanced FGr4D and FGr4B; the classic FGr4S and FGr4P do not include it.

Where to Buy Flysky AFHDS3 Receivers

All four receivers compared in this guide are in stock at SoarSky with fast shipping. Pick your model below:

FGr4D ($37.99) — enhanced, dual built-in antennas, PPX6: Get FGr4D
FGr4B ($35.99) — enhanced, ultra-compact, external antenna, PPX6: Get FGr4B
FGr4S V2 ($29.99) — classic, built-in single antenna, lightest at 5.1g: Get FGr4S
FGr4P ($28.99) — classic, 150mm antenna, best budget pick: Get FGr4P