Tutorial video from Silverback Airsoft showing how to do a hop-up rubber swap on the TAC-41 GBB... "This tutorial video show how to swap the hopup rubber (GBB type,  optional hopup). Changing the hopup rubber will affect the muzzle energy of your airsoft gun, users should obey to laws regarding ownership of airsoft guns in their country.

SBA-HOP-31, 'GBB' hopup unit for TAC-41 includes:

Silverback Airsoft announced that the TAC-41 P (Polymer) bolt action airsoft rifle is soon to be released. Many are expecting the release this summer, just in time for the airsoft season, depending on Covid-19 restrictions.