Astronomical telescope hand screw large screw head hand screw M3 and M4 screws

All metal astronomical telescope hand screw
The product is a large screw head with a diameter of 10MM and a length of 10MM, compared to ordinary ones with a diameter of 6-7MM and a length of 6
-7MM needs to be larger by a large circle, making it easy to tighten by hand
Mainly used for locking on the adapter rings of eyepieces, magnifying glasses, and zenith mirrors
Size:
M3, Length: 8, 10, 12, 15, 20, 30mm
M4， Length: 10, 12, 15, 20, 25, 30mm
The length is the thread length.