 There are many different kinds of suspension seatposts, not to be confused with dropper seatposts, operating on a variety of different mechanisms.Different designs of suspension cause the seat to move in different paths during the compression.The most basic suspension seat post, a piston style, like the one pictured on the side, uses a sliding post with spring pressure that is often changeable by adjusting a threaded insert in the bottom of the post to adjust the preload on the spring.