Received a Panavise 217 today. I already had an older version of the larger 315 and it works great. I wish I could say the same about the Panavise 217. Mind you, the construction is solid, the parts fit together as intended, etc. However, the 315 has screws that hold the levers in place during use. The 217 has these little spring loaded swing arms that somehow have to keep the arms from sliding down the main beam. You are completely useless. You can compress them (according to the instructions)