My cassette is a 7-speed & so is the shifter I'm asking about. The reason I ask is that I got a SRAM TRX 7-speed trigger shifter that doesn't work-skips over 2 gears from 1 shift click & stcks in 1st & 2nd-and I'm sure it's a compatability issue because I sent the 1st one I got back as a defect and the replacement was as bad as the 1st one. Point being it seems like there's more to it than simply matching 7 to 7.