The Sulzer MixPac 9-thread-count Retaining Nut is used to close and seal cartridges that use 9-thread-count threads for mixing nozzles and sealing caps.
This turns out to be the standard thread for most 2-part cartridges, including the Sulzer MixPac C-System and Nordson 2K cartridges. Which are the two most popular cartrdige designs among 2-part cartridges.
Sulzer MixPac Part Number: UMG 10-01-01
It is made to hold in place un-threaded mixing nozzles onto threaded, larger dispensing cartridges (200ml, 400ml, 600ml, and 1500ml). As well as for ALL 14-thread-count Nordson Ratio-Pak style cartridges.