40A40 sprockets are a ANSI standard size that has 40 teeth and works with #40 roller chain. These sprockets are known as a "Type A", which is a
hubless roller chain sprocket. Our 40A40 plate sprockets are a durable, high strength sprocket that is manufactured from 1045CD carbon steel. After manufacturing,
the teeth are hardened to help minimize wear, then a black oxide finish is applied for corrosion resistance.