For better performance of the hop-up chamber, Airtech Studios developed that R-Hop and Flat-Hop Tensioner Nub Set that can be found at Airsoft Atlanta... "The first version is used for RHOP setups for the optimum amount of push onto the patch and BB. Secondly, the nub is used for Flat-Hop setups.
HPA-airsoft users can check out these Ninja Air Tanks at Airsoft Atlanta... "New Ninja Paintball 90/4500 carbon fiber tanks in Olive Drab Green are in stock. Same quality as a the legendary Grey Ghosts, but now in awesome green! Perfect for airsoft! V2 ProReg and standard regulators for SLP and non-SLP rigs (4 choices)."