This is the distinctive Remote Needle Alloy Cap and 'Prayer Book' spring fitted to Amal RN Remote Needle carburettors - the two components listed as a matching pair. Together, they fit over the Remote Needle part of the main body alloy casting of the main Amal RN body. This listing is for both components.
We also sell the spring seperately, if you already have the cap - this is Item listing 0805.
The alloy cap is CNC manufactured by us from an original pattern, including the distinctive milled side - that allows it to fit snugly in the original RN casting
The spring holds the alloy cap in place to stop and stops it flying away in use, it is retained by the knurled top ring - as shown in the photograph of an original RN carburettor with the Cap/Spring fitted.
Sorry this assembly is not cheap - but as well as CNC setup costs, I have had a batch of this distinctive spring specially made from an original pattern, and they were very expensive. I hope you will think them worth the cost - given they are a very rare part to find and almost always missing when you purchase an original Amal RN carburettor