Bagpipe Bag of Bagpipe Holding That Holds Only Bagpipes

The bagpipe bag of bagpipe holding has one purpose and one purpose only: to hold bagpipes. It can hold an infinite amount of bagpipes and nothing else. If someone attempts to put a non-bagpipe item inside the bag, it will be ejected from it at escape velocity. Items ejected from the bag this way at as if they were under the effects of the spell Catapult. If the spell is not aimed at anyone, it will leave the atmosphere. 

This bag resembles the tartan bag of a bagpipe without all of the pipes sticking out of it. It weighs 15 pounds no matter how many bagpipes are inside it.