- 100% genuine cowhide vegetable tanned leather patch blank. Perfect for ball caps, beanies, stockings and more! - Patches include iron-on glue backing and can be applied with a heat press or regular household iron. DIRECTIONS: recommended GF settings: medium natural leather. If you have char marks after engraving, patch can be cleaned up with a magic eraser or baby wipe. You can also apply a thin, even layer of a clear coat spray to seal in the engraving if you choose to do so (ex: Rust-Oleum 2X gloss clear coat). Before adhering patch to hat/stocking/etc, place tea towel in-between patch and iron. We recommend pressing patches using high heat for 5-10 seconds.