I designed this to help tell resistors apart. The holder spaces the resistor wires across 3 breadboard holes. They are designed to replace THESE RESISTORS.
I included multiple resistance values and 2 blank holders (.stl & .step) so you can make your own.
My prototype that ended up working perfectly was printed on an Ultimaker S5 in ABS, then I just colored the number with a blue sharpie. You can also change the filament color mid print for a cleaner result.
I hope this model will help people solve the same problem I had. Being able to tell which resistor is which, and putting the resistor in the breadboard, which can sometimes be tricky.