XR-12 This is a new high performance extra thick air dry filler designed for use on deeper cracks in leather it can also be used over other air dry fillers to level them out. This product has a thicker viscosity and will provide an extremely durable and flexible repair.. Once fully dry you can lightly sand with 6oo grit sand paper and apply a texture with Grain-X spray grain or Texture Paste. You can also apply XR-10 over the repair to fix pin holes or give a smoother finish. Then finish with color This product is part of the XR series extreme repair products.