Hey there, Foredom tool users! If you're working with a SR, TX, L, CC, S, or R series motor and need a replacement outer sheath, this S-77 model is what you're looking for. It's the standard 36-1/4 inches long (about 92 cm) sheath that comes on the Series LX motors. The cool thing about this one is it's made from neoprene, which is way more flexible than the standard sheathing material. That extra flexibility can make a big difference when you're doing detailed work and need the handpiece to move easily. Just a super important note: this sheath is designed to be used with the S-93 key tip inner shafts (those are sold separately, so make sure you have one). Also, double-check your motor—this sheath WON'T fit on the discontinued EE, GG, MMG, F, JJ, or JB motors, or the 975, 980W, and 981W motors. But for the compatible series, it's a direct replacement to get your flexible shaft tool back in smooth, working order. A must-have part for your workshop!