Related Products Expanding drums, 6″ x 2.5″ $160.00 excl GST Flat diamond grinding wheel 6” x 1.5” 600 grit $175.00 excl GST 12 x 12mm diamond bands, soft type 200 grit $18.00 excl GST 12mm diamond band mandrels $12.00 excl GST 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.