ISO 7045 Pan head screws with type H or type Z Cross recess - Product grade A specifies a Recess No. 0 for an M1.6 screw. For this drive size, the recess width is 1.6 mm ref for a Type Z and 1.7 mm ref for a Type H, and the penetration is 0.65 mm to 0.90 mm for Type Z and 0.70 mm to 0.95 mm for a Type H.