isnt that the one made by Airsoftpro.cz?
You should have two small orings in it, one in the front and one in the back. They give you additional airseal around the hopup rubber and the nozzle.
I'm using this hopupunit with an A+ REAPS hopup and Promy barrel, the seal between the HU unit and the nozzle is just 100% :cheers:
Dont worry about the "missing" spring, its not supposed to be there
The HU rubber itself should have enough force to push the arm up. To make sure, I installed an additional oring under that "metalring" wich you use from your old HU unit. Seems to help keeping the HU setting also
You should have two small orings in it, one in the front and one in the back. They give you additional airseal around the hopup rubber and the nozzle.
I'm using this hopupunit with an A+ REAPS hopup and Promy barrel, the seal between the HU unit and the nozzle is just 100% :cheers:
Dont worry about the "missing" spring, its not supposed to be there
The HU rubber itself should have enough force to push the arm up. To make sure, I installed an additional oring under that "metalring" wich you use from your old HU unit. Seems to help keeping the HU setting also
