Here we have given the tool size only for metric thread bolts.
Allen key sizes for grub screws.
The internal wrenching drive used to seat a headless grub screw can be either a hex socket as in allen keys you ll need to know the correct allen key sizes for grub screws which can usually be found on the packaging a star torx socket a square socket known as a robertson drive or a regular slotted drive.
Grub screw 240 pcs hex head allen screw set m3 m4 m5 m6 m8 with 5 small allen key wrench m1 5 m2 m2 5 m3 m4 stainless steel assortment fasteners kits 5 0 out of 5 stars 2 cup point grub screws mixed 40 pack 6mm length various metric threads m3 m4 m5 m6.
We have given a table for your easy selection of proper size of tools.
Refer the following table for metric allen key sizes and dimensions for corresponding socket head cap screw based on iso 4762 din 912 standards.
Hold on to it or post it somewhere in the garage where you can hold up the key or socket screw head to the physical picture this can help you to determine which size of allen wrench you need or have on hand.
For example for an m8 socket head cap screw we need at least 32 8 head size 40mm clearance above the screw for easy accessibility.