The carabiner hook is made of rust-proof stainless steel. It opens reliably and there is no splintering breaking in case of overloading - just like a real safety lock must be!
The integrated safety element - the rubber predetermined breaking point - yields in case of overloading before headcollar or rope is damaged or the animal is injured. Should the horse step on the loose rope, the rubber element also tears and the carabiner hook remains on the holster.