Gridfinity Spade 8+1 Bit Holder

This is a 3x4 holder designed for spade bits. It supports imperial (inches) 1-1/2, 1, 7/8, 13/16, 3/4, 5/8, 1/2, 3/8. There is an extra 1 inch slot, for all those folks that have an extra spade bit, but don't know where it came from.