Round Body vs. Square Body Air Cylinders Round Body vs. Square Body Air Cylinders itriedtorotate (Mechanical) (OP) 23 Apr 15 18:08 Why do people choose either round body or square body cylinders? I don't know what the design benefits are. Is one cheaper? Does one design provide more support? RE: Round Body vs. Square Body Air Cylinders MikeHalloran (Mechanical) 24 Apr 15 00:18 Round end caps are usually lighter and cheaper. Square end caps are easier to bolt to something. Mike Halloran Pembroke Pines, FL, USA RE: Round Body vs. Square Body Air Cylinders btrueblood (Mechanical) 27 Apr 15 17:27 Star for Mike, he nailed it again. I would only add - round bodies are also slightly more compact, and occasionally they fit better into tight spaces.