Printed in TPU, these are inserts to store, and protect, the anodized aluminum parallel guides. You can find them on Amazon, I bought mine from Ali express.
This is designed to fit inside of the Harbor Freight STOREHOUSE 20-Bin Medium Portable Parts Storage Case. There was some space left over so I added bins.
If you decide to print this for yourself, it would be really cool to see your make.
The main body inserts were lengthened 3mm to fix a gap in my printed inserts.
The author marked this model as their own original creation.