German Sprocket wheels had the outer, teethed,  ring replaceable and the new sets from T-Rex represent these disassembled wheels plus some idlers as well.

All have been 3D printed.

There are different sets for vehicles and kits as follows:

#35031 Panther Disassembled Sprocket Set A

#35032 Panther Disassembled Sprocket Set B for all brands

#35033-1/2 PzKpfw III Disassembled Sprocket Set A for DML and TAMIYA

#35034 PzKpfw III Disassembled Sprocket Set B

#35035 PzKpfw III Disassembled Idler for all brands

#35036 PzKpfw IV Disassembled Sprocket Set A Late Version for all brands

#35037 PzKpfw IV Disassembled Sprocket Set B for all brands

#35039 PzKpfw IV Disassembled Idler Casted Version for all brands

#35040 PzKpfw IV Disassembled Idler Welded Version for all brands