EK-ACF Fitting is a more secure variant of the tubing fitting connector as the locking ring prevents flexible tube to be pulled out of the fitting by compressing the tubing wall underneath the ring. Such fitting does not require any hose clamp or similiar substitute. The barb is made of nickel-plated CNC machined brass and the ring is made of anodized CNC machined aluminium. Fittings feature quality rubber O-rings. These fittings are fully compatible with EK-AF series (45°/90°) angled adapters. These fittings sport low-profile design hence it is mandatory to secure the fitting barb using Allen Key 8mm (not included, available for separate purchase) to prevent skin damage to the finger tips - barb has no finger grip surface. Made in Slovenia - Europe!