Thumb screws are designed to be tightened and loosened by hand. Large head diameter makes it easy to access and tighten.
The thumb screw has a straight knurled surface on its head. This gives it better gripping surface, making it easier to tighten or loosen the fastener manually.

Item Specifics
Thread Size        M4 x 12.46mm
Total Length        20mm 
Material                 Brass
Package Content    4pcs x Thumb Screw
Color                  Gold
Head Diameter 10.15mm 

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