STP212 - 2 Gauge x 1/2" (13 mm) Self Tappers Pan Head Pack of 10

STP212 - 2 gauge x 1/2" (12.5 mm) Self Tapping Screws - Pan Head Phillips - 304 Stainless Steel -  Pack of 10

Always have some of these handy.

2 Gauge thread size is 2.25mm outside diameter.