PE (Polyester Resin) Each hold has a Stainless Steel Duel Fixing Insert that will not rust or corrode, unlike most other climbing holds. Made from Polyester Resin, this is the most durable, trusted and reliable material that has been used to produce climbing hols for decades.. These holds are the UK industry standard for use 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. • Larger holds are hollow so that weight is reduced further. • Stainless Steel Duel Bolt inserts for increased life and appearance. • All holds (except smallest footholds) have more than one screw hole for anti spinning • Holds are colourfast and resistant to U.V. • Reinforced with sand to add strength and reduce wear.. • Manufactured in the European Union, reducing the carbon footprint.