1,DSLR support rods 2, carbon fiber rods 3, 3k sanded smooth surface ... length, twist resistance.length in 50mm, 80mm, 100mm, 150mm, 200mm, 250mm, 300mm, 350mm, 400mm, 450mm, etc. wall thickness is usually 2mm ... -looking, smooth sanded to make sure the smooth movement. DSLR support rods