Coil set for grid dip meter?

[Avery W3AVE]

Could be for something else, I suppose. Cardboard maroon coil holder matches ‘50s Heath GD-1A and B, but those dippers had four coils and this set has five plus a link. Four are labeled: 2-5 MC, 5-14 MC, 14-37 MC, and 37-100 MC. A coil for lower frequencies (looks like a pie-wound choke) and the link are unlabeled. Could be a homebrew set but the holes in the insert look custom made to fit the coils and connecting pins. VG condition. $15 plus shipping.