---
product_id: 155720618
title: "S SYDIEN 4Pcs 4mm Rigid Flange Shaft Coupling Motor Guide Shaft Coupler Connector"
price: "€ 18.56"
currency: EUR
in_stock: true
reviews_count: 7
url: https://www.desertcart.nl/products/155720618-s-sydien-4pcs-4mm-rigid-flange-shaft-coupling-motor-guide
store_origin: NL
region: Netherlands
---

# M3 fastening & base screw holes 4mm inner diameter precision fit Hardened electroplated alloy steel S SYDIEN 4Pcs 4mm Rigid Flange Shaft Coupling Motor Guide Shaft Coupler Connector

**Price:** € 18.56
**Availability:** ✅ In Stock

## Summary

> ⚙️ Lock in precision, power your projects with confidence!

## Quick Answers

- **What is this?** S SYDIEN 4Pcs 4mm Rigid Flange Shaft Coupling Motor Guide Shaft Coupler Connector
- **How much does it cost?** € 18.56 with free shipping
- **Is it available?** Yes, in stock and ready to ship
- **Where can I buy it?** [www.desertcart.nl](https://www.desertcart.nl/products/155720618-s-sydien-4pcs-4mm-rigid-flange-shaft-coupling-motor-guide)

## Best For

- Customers looking for quality international products

## Why This Product

- Free international shipping included
- Worldwide delivery with tracking
- 15-day hassle-free returns

## Key Features

- • **Premium Hardened Alloy:** Heat-treated and electroplated steel offers superior hardness, anti-rust, and oil resistance.
- • **Robust Fastening System:** Dual M3 screw holes provide secure, vibration-resistant coupling under demanding conditions.
- • **Precision Engineered Fit:** 4mm inner diameter ensures seamless shaft alignment for flawless motor performance.
- • **Versatile Industrial Use:** Ideal for RC models, motor shafts, and custom mechanical projects—engineered for professionals who demand reliability.
- • **Compact & Lightweight Design:** Small 10mm x 10mm cylinder size fits tight spaces without compromising strength.

## Overview

The S SYDIEN 4Pcs 4mm Rigid Flange Shaft Coupling set features four high-quality, heat-treated alloy steel couplers with precise 4mm inner diameters and dual M3 fastening holes. Designed for superior shaft alignment and durability, these compact couplings resist rust and oil, making them perfect for RC motors, industrial applications, and custom mechanical builds where reliability and precision matter.

## Description

S SYDIEN 4Pcs 4mm Rigid Flange Shaft Coupling Motor Guide Shaft Coupler Connector: desertcart.com: Industrial & Scientific

Review: Not the use intended, but worked great! - I'm sure I'm the only one that's ever used these to do what I did, so take it with a grain of salt b/c this use-case is very much 'not as intended'. I used one of these to make a dirtbike powervalve-actuator-shaft collar. How to explain.. hmm... My old dirtbike, a KX250, 2-stroke, has a mechanism called a power-valve. W/out going into gory detail, this is a set of valves that are mechanically moved by an engine-driven centrifugal spindle as RPM increases. This affects the power-output curve of the motor. So anyway, the output-arm of this spindle normally engages with a 'flanged collar' that looks like a small metal pulley or spool. The arm moves in an arc and pushes/pulls this spool which is loosely connected to a shaft that does the valve actuation via two 'e-clips'. On my bike, this spool/pulley went missing (b/c the outer e-clip failed). The part is no longer sold by manufacturer. Finding used ones is nigh impossible. There's no close-analog part I could find in searching McMaster-Carr and the like. I still search occasionally to see if there is something that already exists. You'd think 'dual-flanged metal spool' would be a common part. So, I made one. I found these items in a desperate search. The 5mm shaft diameter is almost perfect.. I had to ream it out maybe .05mm or so to give it just enough clearance on shaft so it would spin freely. The tricky part was that I had to narrow the 'body' and then weld on another larger-diameter washer so that it would mimic the spool I needed. So, picture one of these with another larger diameter flange on the side that doesn't have one (like a 'round-wing' Tie Fighter). The whole thing, outside of flange-to-flange has to be like 8mm (inner spacing is ~4mm), so I couldn't just use 2 end-to-end. I managed to get it shortened and welded on a flat washer of same diameter... and I'll be damned if it doesn't work! It looks like hell, but it works and at the end of the day, wasn't all that hard to make. Now that I've made one, if I had to do it again, it'd be easier. I now have 3 spares to work with too.
Review: Works - Works

## Features

- Package Content:4Pcs Flange Shaft Couplings with 1Pc Mini Hex Wrench with Some Fastening Screws. Inner Diameter:4mm/0.16''.Fastening Screw Hole:M3.Base Fixing Screw Hole:M3.Cylinder Outer Diameter:10mm/0.39''.Cylinder Height:10mm/0.39''.Base Diameter:22mm/0.87''.Base Height:2mm/0.08''
- HIGH QUALITY:Made of fine plating steel which is hardened by heat treatment and electroplated.Its hardness is more better than ordinary copper and aluminum alloy material. Anti-oil and anti-rust
- LOW INERTIA:Flange shaft couplings is so highly sensitive that can quickly switch the working state
- EXCELLENT PERFORMANCE:Compact structure and small size.It can effectively ensure the alignment of two shafts
- WIDELY USE:Suitable for model shaft connection,perfect accessories for RC model motor,etc

## Technical Specifications

| Specification | Value |
|---------------|-------|
| Color | 4mm |
| Exterior Finish | Steel |
| Fastener Type | Flange |
| Material | Alloy Steel |
| Metal Type | Alloy Steel, Aluminum, Copper |
| Thread Size | M 3 |

## Product Details

- **Material:** Alloy Steel
- **Fastener Type:** Flange
- **Thread Size:** M 3
- **Exterior Finish:** Stainless Steel
- **Color:** 3mm

## Images

![S SYDIEN 4Pcs 4mm Rigid Flange Shaft Coupling Motor Guide Shaft Coupler Connector - Image 1](https://m.media-amazon.com/images/I/51OE+K-N38L.jpg)
![S SYDIEN 4Pcs 4mm Rigid Flange Shaft Coupling Motor Guide Shaft Coupler Connector - Image 2](https://m.media-amazon.com/images/I/51cO61SMUUL.jpg)
![S SYDIEN 4Pcs 4mm Rigid Flange Shaft Coupling Motor Guide Shaft Coupler Connector - Image 3](https://m.media-amazon.com/images/I/51t5M0m8lPL.jpg)
![S SYDIEN 4Pcs 4mm Rigid Flange Shaft Coupling Motor Guide Shaft Coupler Connector - Image 4](https://m.media-amazon.com/images/I/61jtrOkHyhL.jpg)
![S SYDIEN 4Pcs 4mm Rigid Flange Shaft Coupling Motor Guide Shaft Coupler Connector - Image 5](https://m.media-amazon.com/images/I/71BMddFrl0L.jpg)

## Customer Reviews

### ⭐⭐⭐⭐⭐ Not the use intended, but worked great!
*by A***R on November 8, 2023*

I'm sure I'm the only one that's ever used these to do what I did, so take it with a grain of salt b/c this use-case is very much 'not as intended'. I used one of these to make a dirtbike powervalve-actuator-shaft collar. How to explain.. hmm... My old dirtbike, a KX250, 2-stroke, has a mechanism called a power-valve. W/out going into gory detail, this is a set of valves that are mechanically moved by an engine-driven centrifugal spindle as RPM increases. This affects the power-output curve of the motor. So anyway, the output-arm of this spindle normally engages with a 'flanged collar' that looks like a small metal pulley or spool. The arm moves in an arc and pushes/pulls this spool which is loosely connected to a shaft that does the valve actuation via two 'e-clips'. On my bike, this spool/pulley went missing (b/c the outer e-clip failed). The part is no longer sold by manufacturer. Finding used ones is nigh impossible. There's no close-analog part I could find in searching McMaster-Carr and the like. I still search occasionally to see if there is something that already exists. You'd think 'dual-flanged metal spool' would be a common part. So, I made one. I found these items in a desperate search. The 5mm shaft diameter is almost perfect.. I had to ream it out maybe .05mm or so to give it just enough clearance on shaft so it would spin freely. The tricky part was that I had to narrow the 'body' and then weld on another larger-diameter washer so that it would mimic the spool I needed. So, picture one of these with another larger diameter flange on the side that doesn't have one (like a 'round-wing' Tie Fighter). The whole thing, outside of flange-to-flange has to be like 8mm (inner spacing is ~4mm), so I couldn't just use 2 end-to-end. I managed to get it shortened and welded on a flat washer of same diameter... and I'll be damned if it doesn't work! It looks like hell, but it works and at the end of the day, wasn't all that hard to make. Now that I've made one, if I had to do it again, it'd be easier. I now have 3 spares to work with too.

### ⭐⭐⭐⭐⭐ Works
*by M***K on June 15, 2025*

Works

### ⭐⭐⭐⭐⭐ What I wanted
*by D***D on November 13, 2024*

Well made very good quality

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---

*Product available on Desertcart Netherlands*
*Store origin: NL*
*Last updated: 2026-02-13*