Model of the common 1-2-3 Block setup tool found in machine shops all over the world. The name 1-2-3 comes from the block's dimensions: 1" x 2" x 3". The holes are 3/8" in diameter. While an FDM 1-2-3 Block probably isn't precise enough for machine shop work it make for an interesting print.

Print instructions

Should print in any material with any settings you want. I've printed it with a 0.6mm nozzle at 0.3mm layer height in PLA.