Bezerk RC option part for the Team Associated B74 4wd buggy. This is a battery retention system that offers a few options. Two different hold downs, o-ring for a quick removal that tends to clamp the battery slightly. A tab system like our Touring Car mounts to allow more flex in the chassis. The tabs should be spaced up a hint higher than the top of your pack for best results so that it can float under the tabs. The front and rear hooks can be swapped around front to rear for different battery positions, eg short hook at front for battery forward or short at back for rearward weight bias. Two different lengths of the long hooks accommodate the use of either a standard shorty pack or the newer lower profile packs. Hooks made from 2.5mm carbon fiber and the tabs from 3.0mm carbon fiber. One o-ring comes with each kit.