PU (Polyurethane) Each hold has a Stainless Steel Duel Fixing Insert that will not rust or corrode, unlike most other climbing holds. Made from Dannomond’, a new super PU developed and tested at the busiest climbing centre in the UK, ‘test sample 875’ finally made the grade. This is the hardest Polyurethane available and more durable than all previous versions of all other Polyurethane holds. These holds will not break under the heavy work load which is now standard in a busy commercial climbing centre / climbing gym. Conforms to European Standard EN 12572-3 Our new texture using a more complex and open grain that still grips when clogged up with chalk. Better for your skin.