Theoben Rapid Forum

I thought I would put on a pic showing the difference between the bottle adaptors on early and later mk1s.....

The early mk1 uses a shorter bottle adaptor with a gap in the threads as that is where the porting is to the valve chamber

The later mk1 uses a longer bottle adaptor that's the same length as a regulator body - so that all of the later stocks could be used - there isnt a gap in the threads on this bottle adaptor as the later blocks have the porting to the valve chamber further back that is clear of the threads