Color, non-stick coating:
Amana Tool® dowel drills are coated with a special PTFE, a non-stick color coating, in case where the carbide tip cutting edges are coated, there is no need to sand the coating off before use.
Once the tool starts drilling, the coating is cleared off the needed cutting edge right away.
Amana Tool dowel drills coating is applied onto the bit at a temperature of 570° F.
That coating reduces the friction between the chip and the body inside the flute and it helps to clear the chips out of the hole during the drilling creating cooler drilling area, no burning and longer lasting bit cutting edge.