The Rollerblade REVV Cuff Buckles and Straps (2) come in a pair with the screws and hardware to install so that you can replace or upgrade your existing buckles with ease.

These are the top buckles used on Rollerblade REVV Skates. They may also work on other brands, but these are No Receiver Two-Point Mount Buckles.  The strap screws onto the inside of the boot without a receiver (or receptor). It does include screws and hardware to install.
 
Two-Point Cuff Buckles WITHOUT Receiver (2BM). The buckle mounts to the outside of the boot at one point as does the strap on the inside of the boot. There are no receivers (or receptors).