Description: Material: 6063 aluminum alloy [10x10mm]: outer size 10*10mm, inner hole size 7*7mm, wall thickness about 1.5mm [20x20mm]: outer size 20*20mm, inner hole size 16*16mm, wall thickness about 2mm [30x40mm]: outer size 30*40mm, inner hole size 26*34mm, wall thickness about 2mm Length select: 100mm 150mm 200mm 400mm Package include: According to your choice.
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