[https://www.amazon.com/dp/B077D9GSVK?tag=dmflip-20&linkCode=ogi&th=1&psc=1]
Caplugs SQR-5-3-10 – SQR Series – Plugs for Square Tubing, 15 Pack, to Fit Square Tube OD 5.000″ x Height 0.98″, Wall Thickness 3-10 Ga. (.259-.134″), PE-LD, Black, Exterior Ribs (99192477)
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