---
product_id: 411231093
title: "Kair Straight 125mm to 100mm Ducting Reducer/Adaptor - SYS-125 / SYS-100 - DUCVKC603 by Kair"
brand: "kair"
price: "¥3740"
currency: JPY
in_stock: true
reviews_count: 5
category: "Kair"
url: https://www.desertcart.jp/products/411231093-kair-straight-125mm-to-100mm-ducting-reducer-adaptor-sys-125
store_origin: JP
region: Japan
---

# 125mm to 100mm precision fit Universal compatibility with SYS-100 & SYS-125 Made in UK, premium quality plastic Kair Straight 125mm to 100mm Ducting Reducer/Adaptor - SYS-125 / SYS-100 - DUCVKC603 by Kair

**Brand:** kair
**Price:** ¥3740
**Availability:** ✅ In Stock

## Summary

> 🔧 Upgrade your airflow game with precision and style!

## Quick Answers

- **What is this?** Kair Straight 125mm to 100mm Ducting Reducer/Adaptor - SYS-125 / SYS-100 - DUCVKC603 by Kair by kair
- **How much does it cost?** ¥3740 with free shipping
- **Is it available?** Yes, in stock and ready to ship
- **Where can I buy it?** [www.desertcart.jp](https://www.desertcart.jp/products/411231093-kair-straight-125mm-to-100mm-ducting-reducer-adaptor-sys-125)

## Best For

- kair enthusiasts

## Why This Product

- Trusted kair brand quality
- Free international shipping included
- Worldwide delivery with tracking
- 15-day hassle-free returns

## Key Features

- • **Durable UK Craftsmanship:** Constructed from high-quality polystyrene/polypropylene, built to last in temperatures from -15°C to 60°C.
- • **Hassle-Free Installation:** Lightweight, compact design with easy sealing options for both rigid and flexible ducting setups.
- • **Seamless Size Transition:** Effortlessly converts 125mm ducting to 100mm for perfect airflow integration.
- • **Plug & Play Compatibility:** Fits over push-fit connectors and straight ducting, compatible with Kair’s extensive SYS range.
- • **Versatile Ventilation Solution:** Ideal for tumble dryers, extractor fans, hydroponics, cooker hoods, and HVAC systems.

## Overview

The Kair Straight 125mm to 100mm Ducting Reducer/Adaptor (DUCVKC603) is a high-quality UK-made plastic fitting designed to seamlessly connect 125mm female spigots to 100mm male ducting. Compatible with Kair’s SYS-100 and SYS-125 ducting systems, it supports a wide range of ventilation applications including tumble dryers, extractor fans, and HVAC setups. Engineered for durability and ease of installation, it operates reliably within -15°C to 60°C, ensuring efficient airflow management in both residential and professional environments.

## Description

Kair 125mm Female to 100mm Male Round Ducting Adaptor. Made in the UK using high-quality white Polystyrene/Polypropylene plastic Material. Max / Min Temperature: +60c / -15c; On one side there is a 125mm Female Spigot - Will fit over male fittings (bends etc). Rigid round 125mm ducting pipe (Part: DUCVKC267) will require a male connector / coupling (Part: DUCVKC355). 127mm Flexible ducting (Part: DUCP0092/127/35) will fit over and require tape or metal hose clips (Part: DUCVKC611) to seal. ;On the other side there is a 100mm male spigot - will fit into 100mm straight ducting (part: DUCVKC250). Can be used with rigid plastic ducting systems - seal with mastic or tape. Can be used with flexible ducting systems with use of metal hose clips (Part: DUCVKC264). Kair plastic rigid ducting is perfect for DIY and trade use. Perfectly suited for ducting your Tumble Dryer, Bathroom or Kitchen extractor fan, Hydroponics, In-Line Extract Fans, or Cooker Hood. This reducer can be used as a part of a long ductwork run for a variety of purposes including whole house ventilation, passive stack vent, positive input, air conditioning, HVAC, and Heat Recovery Systems. ;Genuine Kair Product & covered by the Kair 100% Satisfaction Guarantee for your peace of mind. Made in the UK. Compatible with the extensive Kair SYS-100 & SYS-125 range of fittings, outlets, and grilles. Search for Kair SYS-100 Ducting for the full range of Kair 100mm Round and 110mm x 54mm Rectangular Ducting Products. Search for Kair SYS-125 for the full range of Kair Rectangular 150mm x 70mm and 125mm Round ducting products.

Review: perfetto e funzionale - il riduttore è un pezzo molto semplice ma trovarlo in giro diventa complicato i negozi non lo tengono e tanto meno le ferramente, qui è diventato tutto semplice e si adatta perfettamente ai tubi da ridurre
Review: La disponibilité - On avait pas ce produit en quincaillerie. J avais acheté une hotte et oh non!! Les normes ont changées. La solution était de repercer un mur de 1.5 m en briques ( des heures de travail😣) au dernier moment j ai penser à desertcart et 8.00€ et 1 jour plus tard ma hotte est poser et en état de fonctionnement.😥

## Features

- Adapter to convert 125mm to 100mm ducting - 5" to 4"
- On one side there is a 125mm female spigot. Fits over push-fit connectors (bends, etc.) Requires an additional 125mm plug to connect round 125mm pipe.
- On the other side there is a 100mm spigot. Fits in 100mm straight ducting
- Compatible with 100mm and 125mm ducting systems, including the extensive Kair SYS-100 and SYS-125 range of fittings, sockets and grilles.
- Perfectly suited for conducting your tumble dryer, bathroom or kitchen extractor fan, hydroponics, in-line fans or cooker hoods and other ventilation applications.

## Technical Specifications

| Specification | Value |
|---------------|-------|
| ASIN | B004X4S7QI |
| Best Sellers Rank | #58,930 in Tools & Home Improvement ( See Top 100 in Tools & Home Improvement ) #75 in Heating & Cooling Ducting Products |
| Brand | Kair |
| Brand Name | Kair |
| Color | White |
| Colour | White |
| Connector Type | Reducer |
| Connector type | Reducer |
| Customer Reviews | 4.5 out of 5 stars 2,507 Reviews |
| Item Dimensions | 5.1 x 5.1 centimeters |
| Item Weight | 0.09 Pounds |
| Item dimensions L x W x H | 5.1 x 5.1 centimeters |
| Item height | 0.01 centimeters |
| Manufacturer | Kair |
| Material | Plastic |
| Material Type | Plastic |
| Model Number | DUCVKC603 |
| Number of Pieces | 1 |
| Size | Klein |
| Thread Size | 125mm, 100mm |
| Unit Count | 1 Count |

## Product Details

- **Brand:** Kair
- **Colour:** White
- **Item dimensions L x W x H:** 5.1 x 5.1 centimeters
- **Material:** Plastic
- **Size:** Klein

## Images

![Kair Straight 125mm to 100mm Ducting Reducer/Adaptor - SYS-125 / SYS-100 - DUCVKC603 by Kair - Image 1](https://m.media-amazon.com/images/I/415Hw3eWTlL.jpg)

## Customer Reviews

### ⭐⭐⭐⭐⭐ perfetto e funzionale
*by B***O on 10 May 2016*

il riduttore è un pezzo molto semplice ma trovarlo in giro diventa complicato i negozi non lo tengono e tanto meno le ferramente, qui è diventato tutto semplice e si adatta perfettamente ai tubi da ridurre

### ⭐⭐⭐⭐⭐ La disponibilité
*by D***A on 12 June 2018*

On avait pas ce produit en quincaillerie. J avais acheté une hotte et oh non!! Les normes ont changées. La solution était de repercer un mur de 1.5 m en briques ( des heures de travail😣) au dernier moment j ai penser à Amazon et 8.00€ et 1 jour plus tard ma hotte est poser et en état de fonctionnement.😥

### ⭐⭐⭐⭐⭐ Riduttore come da aspettative
*by F***I on 16 February 2018*

Il pezzo è perfettamente in accordo alla descrizione e rispetta le aspettative. Buona sia manifattura che i materiali utilizzati. Lato 125mm il componente ha la dimensione del tubo, quindi per una eventuale connessione ad un tubo occorre prevedere un raccordo.

## Frequently Bought Together

- Kair Straight Ducting Reducer/Adaptor - SYS-125 / SYS-100 - DUCVKC603 125 mm to 100 mm Kair
- Kair PVC Flexible Hose 125mm - 5 inch Universal Tumble Drier, Cooker Hood, Extractor Fan, Air Conditioner Hose - 3 Metre Length
- 125mm Pack of 2 Adjustable 120-140mm Stainless Steel Pipe Clamp Secure Hose Clip Inline Duct Extractor Fan Cooker Hood

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**Shop now:** [https://www.desertcart.jp/products/411231093-kair-straight-125mm-to-100mm-ducting-reducer-adaptor-sys-125](https://www.desertcart.jp/products/411231093-kair-straight-125mm-to-100mm-ducting-reducer-adaptor-sys-125)

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*Product available on Desertcart Japan*
*Store origin: JP*
*Last updated: 2026-02-23*