SRAM NX Eagle PG-1230 Cassette - 12 Speed, 11-50t, BlackThe NX Eagle PG 1230 cassette gives riders every bit of the climbing range that the Eagle ecosystem affords with a simple upgrade to splined drive body wheels. Designed to be durable enough to withstand the increased demands of E MTB applications and a perfect solution to heavy duty use and abuse. The PG 1230 is the only Eagle cassette that meets durability requirements for E MTB applications Wide 11 50t gear range Compatible with a splined driver