The low price was nice, the threads seem to be at the same taper as that of my Edwards E2M2 pump. However, unlike most other vacuum adapters, there is no lip between the threads and the nut to align and hold an O-ring to make a seal with the pump body. So, I don't think this is a useful part for the vacuum side of the pump.This was not fatal for my use. I only wanted to use it on the vent side of the pump to attach a SIS cat##FK201B Which is an All-In-One filter with Edwards E2M2 Fitting NW25 flSee full review