Related Products 120 grit silicon carbide, 500g pot. $12.00 Diamond lap disk 8” PSA backing 1500 grit $40.00 Diamond point set 20pcs $28.00 12mm diamond band mandrels $10.00 Quantity Add to cart Product added to wishlist. Description 12mm x 12mm diamond bands are an alternative to solid diamond points. This is the expanding mandrel with a 3mm shaft. Add to WishlistProduct added! Browse WishlistThe product is already in the wishlist! Browse Wishlist Share Product code: 400600 Category: Diamond point sets and bands. Tags: diamond bits, Dremel bits, glass, lapidary.