If you want to decorate your edges with a small line. Makes your good more finish.
Edge Creaser 2.0mm
To bevel your edges before burnishing them with wax or Tokonole. I use a #2 for belts.
OWDEN - Leather Edge bevelers - Leather Tool
Tips for a Dremel to help polish your edges. Use Tokonole. You can do it by hand too.
2pcs Leather Burnisher Bits for Rotary Tools, 2 Styles Leather Burnishing Tips Edge Burnishing Tool Polishing Head Accessories for Leather Craft Hand Making
The best way to get finished and protected edges. You can also add bees wax.