SRS / HTI FAST Hop-Up Unit + hopup rubber (SBA-HOP-21)FAST (Field Adjustment SeTting ) hop up for Silverback SRS (all versions) and HTI. 6061 aluminum CNC machining hop-up unit for the Silverback SRS. Allows you to adjust your hop up in-game without any tool, in just a few seconds. This hop-up unit is compatible with most AEG hop-up rubbers and AEG barrels.
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