With the STEELMAN Color-Coded Tread Depth Gauge, you’ll be able to easily identify how much tread depth is left on each tire. The green range is 6/32+ (4.75mm+), the yellow range is 3/32 - 6/32 (2.4 - 4.75mm), and the red range is 0 - 3/32 (0 - 2.4mm).
eBay