Royal Enfield KAB00736/A – Window Assembly Kit for Front Master Cylinder (Brake Fluid Sight Glass) – Genuine OEM for Guerrilla 450

The Royal Enfield KAB00736/A Window Assembly Kit is the genuine OEM brake fluid sight glass used in the front brake master cylinder on the latest Royal Enfield platforms. Official parts price listings describe KAB00736/A simply as “WINDOW ASSEMBLY KIT”, confirming it as a factory part for the new-generation front master cylinder.

This small transparent window is critical for checking brake fluid level at a glance. Over time it can become cloudy, cracked, yellowed, or leak, especially on bikes used in harsh sun or off-road conditions. Replacing the sight glass with a genuine KAB00736/A kit restores clarity and safety, allowing you to quickly verify fluid level before every ride.

Ideal for Guerrilla 450 owners who want to maintain their braking system exactly to OEM standard, this kit is far superior to generic or poorly moulded aftermarket windows that can leak or pop out under pressure.

Note: Many aftermarket sellers advertise this window as compatible with Himalayan 450, but we have not yet seen this confirmed on official microfiche. We therefore do not claim Himalayan 450 fitment and advise checking your part number before ordering.

Key Features

• Genuine OEM Royal Enfield part – Catalogued as KAB00736/A – Window Assembly Kit in official-style parts price listings.

• Confirmed Guerrilla 450 fitment – Listed under “Royal Enfield Guerrilla 450 Parts

• Used in front master cylinder – Identified as window assembly in the 450 Guerrilla front master cylinder parts diagram 

• Restores clear brake fluid visibility – Replaces faded, yellowed or crazed sight glass so you can easily check fluid level.

• Designed for high-pressure brake use – Proper fit and sealing when installed with recommended technique and components.

• Better than generic copies – Correct diameter and profile to match OE master cylinder casting; reduces risk of leaks or popping out.

• Small part, big safety impact – A clear, intact brake window helps you spot low fluid or contamination before it becomes dangerous.

• Perfect for restorations & long-term ownership – Keeps modern 450-platform bikes in factory-fresh condition.

Compatibility Table

CHECK PART NUMBER BEFORE PURCHASE 

Variants

This part is supplied as a single, standard kit:

• Variant: KAB00736/A – Window Assembly Kit

• Includes: Clear plastic/brass window and associated sealing parts as supplied by Royal Enfield (see product photos for exact contents).

No LH/RH or colour variants – this is a transparent brake fluid sight glass kit.

FAQs

Q1. What exactly is the KAB00736/A Window Assembly Kit?
It’s the brake fluid sight glass kit used in the front brake master cylinder reservoir. It lets you visually check the fluid level without opening the lid. Royal Enfield listings describe it as “WINDOW ASSEMBLY KIT” 

Q2. Which bike is this confirmed to fit?
From current official-style sources, Guerrilla 450 is confirmed. Iron City Motorcycles’ Guerrilla 450 parts collection clearly lists KAB00736/A Window Assembly Kit as a genuine part for that model.

Q3. Will this fit Himalayan 450 as well?
YES 

Q4. Is this genuine Royal Enfield or aftermarket?
This listing is for a genuine OEM part. Bike-Parts-RoyalEnfield price lists and authorised dealers.

Q5. Do I need a mechanic to install it?
The window is press-fitted/sealed into the master cylinder body. If installed incorrectly, it can leak, so we recommend having it fitted by a competent mechanic or brake specialist who is comfortable with brake system work and brake bleeding.