These are limited-edition collectible pins produced by Leen Custom Pins. The cars portrayed are vehicles that were displayed at The Ultimate Driving Museum during The Power of M: Celebrating 50 Years exhibit. Each pin was produced in limited quantities of 300, and each pin bears a numerical listing on the back of the pin.
Petronas Z4
Valvoline E36 M3
1972 3.0 CSL
M1 Pro
E30 M3
Valvoline E36 M3 with backing card signed by Bill Auberlen