Cross recessed (+) old JIS raised countersunk head screw Stainless steel Unplated 5 X 12 Pitch 0.8

The top surface of the countersunk head has a rounded shape. While a flat countersunk head can be made flush with the mating surface, sliding something across it may catch on the slot groove or cross recess. An oval countersunk head cannot be made flush, but it prevents snagging on the slot or cross recess. Since the slot groove or cross recess can be made deeper than on a flat countersunk head, it allows for better engagement with a screwdriver.

Although it protrudes more than a flat countersunk head, it can be kept lower in profile compared to a pan head. It is used when you want to avoid excessive protrusion but also do not want a flush finish. Since it resembles a countersunk head with a decorative touch, it is perfectly acceptable to choose it based on design or aesthetics.
Machine Screw Head Dimensions List　How to Measure Countersunk Screws (Nejikuru Facebook)　Oval Countersunk Screw Encyclopedia

• Cross recessed (+) old JIS raised countersunk head screw
• Nominal thread diameter M5
• Length (ℓ) 12.0
• Pitch 0.9
• Cross recess number 2
• Head diameter (dk) Nominal 10 Tolerance 0, -0.6
• Head height (k) Nominal 2.8 Tolerance 0, -0.3
• Chamfer (c) Approx. 0.3
• Head dome height (f) Approx. 1.2
• Head height (k+f) Nominal 4.0 Tolerance 0, -0.5
• Cross recess (m) Reference 5.3
• Cross recess depth (q) Max 3.13 Min 2.58