Model: Knurled Thumb Screws. Thread size ：UNC 1/4-20. Thread length： 3/8"（10mm）, 1/2"（12.7mm）, 5/8"（16mm）, 30mm. Material: Aluminum Alloy 6061. Tolerance range: ± 0.2mm. Note: due to the differences in shooting scenes and technology, there will be a chromatic aberration between the photos and actual colors.
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