Cone Point Grub Screws. Cone point grub screws with allen key drive. M4 x 0.7mm pitch; allen key size 2mm. M2 x 0.4mm pitch; allen key size 0.9mm. M2.5 x 0.45mm pitch; allen key size 1.3mm. M5 x 0.8mm pitch; allen key size 2.5mm.