![Marabu GLH Hardener](http://dtgmart.com/cdn/shop/products/glh-ink-hardener_5c235c56-bb21-454b-acf3-338619c5c086_462x462.png?v=1624323983)
GLH Hardener is recommended for use with Marabu Glass GL Inks only. Add hardener to the ink immediately before printing: 1 part of hardener to 20 parts of the ink (5%). After mixing, the ink can be used for 8-10 hours. Harder is available in 50g bottles.