Filament Sample Spool

Stackable filament sample spool for use of filament samples usualy collected at fairs or promo actions by manufacturers packed previously mostly in tiny flat bag which does not work that much for a prints.
Part B is base
Part C is cover

Internal holding diameter is 50 mm
Diameter of filament winding part is 123,2 mm
Outside diameter of whole thing is 180 mm

Complete item is any count of B's and one C at the end. Count of B's is count of different filaments which it will be able to hold.
Combination could be:
B-C
B-B-C
B-B-B-C ..etc.

Parts should connect well even with some tolerances, i use small ammount of CA glue to hold them together on the ring.