Kinda like a spring.. but restricted to one direction. This comes up when I am building tanks and stuff using modded static weapons that produce recoil, and my entire tank will sometimes do backflips. Definitely not the only use, such as airplane wheels or just a smaller (easier to use) piece of suspension. Maybe conveyed and definitely should have attachment points for blocks (for making large ships kinda sink when the upwards thrust is turned off, similar to when the Millennium Falcon lands). no mods for this either, and having it in the base game would be fantastic.