It's a handmade 30/60 degree precision angle block and the name in it is the name of the toolmaker. The notches in it are in there on purpose so you can use it in a vise on a mill and set your part up that is wider than the thickness of the angle and the angle doesn't slide while you are trying to set your part.
Anyone that has used an angle block to set up a part in a vise knows what I mean. If it doesn't have the notch out you almost need three hands to set a part. It is a very useful tool for a machinist.
And if you have two in the box, the other is most likely a 45 degree angle.