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Aluminum Hollow Rod (5/8") – Modern Studio Equipment.
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Threaded Hollow Stainless Steel Rod 1/16" 1/2 Inch 431 430 410s 416 202 321
Stainless Steel U Bar Stainless Steel C-Bar Small Rectangular Stainless Steel Bar Stainless Steel Hollow Bar - China Stainless Steel Round Bar 310, 420 Stainless Steel Round Bar | Made-in-China.com