What should also be mentioned here is that mild steel/ms tubing D.O.M. comes in .120 wall but the tolerance is +.002 -.004, and most of the time the tubing is on the minus side. I.E. .120 might be as low as .116 and will not certify, SO most chassis/roll cage builders use .134 wall tubing to guarentee that it will certify, that's only a couple lbs. for a full cage and a little security.
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