self - shaf
- self-acting belt tension
- self-acting friction clutch
- self-acting valve
- self-aligning bearing
- self-aligning roller
- self-aligning roller bearing
- self-aligning step roller
- self-closing valve
- self-locking
- self-locking screw
- self-lubricating bearing
- self-packing pipe threads
- self-sealing pipe thread
- self-stopping
