Split pin, stainless steel, nominal size 15mm, length 190mm

Marine grade stainless steel Split pins / cotter pins 316 A4

Please see second photo for specification sheet 

A - (Distance between tip of the longer pin than the shorter pin)
B - (Distance between the top of the round head to the start of the pins)
C - (Outside diameter of round head)
D - Diameter of hole for pins
D1 - (Actual Diameter of pins when closed against each other)
L - (Length of pins only)

So 3.2mm x 40mm would be dmm x Lmm
3.2mm Diameter of hole for pins and 40mm length of pins only without round head 

How to size
1. Measure the hole your split pin is for. ie: a 4mm hole
2. So just purchase a 4mm split pin. It will be slightly smaller and fit perfect. 
3. So the first number of the split pin is actually the size of the hole it is for.