What type of batteries do eTap AXS shift-brake levers require? One CR2032 per shifter. The same as the previous RED eTap™ groupset. See the shifter and controller battery replacement procedure here. Related articles Are SRAM AXS controller (shifter) batteries replaceable? How long do eTap AXS shifter batteries last? How do I update firmware using the AXS App? Are 11-speed SRAM RED eTap derailleur batteries compatible with SRAM RED and Force eTap AXS derailleurs? Is Rival eTap AXS compatible with SRAM RED or Force eTap AXS parts?