Firefighter's carabiner with safety catch DIN 5299D (firefighter's carabiner, carabiner hook) - steel carabiner with a cap nut for secure locking and higher load capacity. Used in the home, workshop, garden, construction, sports, and industry. We offer the carabiner in many modifications - with a safety catch (cap nut), with an eye, strap, egg-shaped or oval. Available in 10 sizes in the 40x4mm - 160x13mm range, surface finish: electroplated zinc, also available in stainless steel.