EK-ACF Fitting (Advanced Compression Fitting) is a soft-tube compression fitting, designed for use with flexible soft tubing such as PVC, EPDM, Norprene, silicone or any other type of compatible flexible tube. 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 and the ring are made of nickel-plated CNC machined brass. 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.Technical data: - thread: G1/4" BSP; 4.5mm male thread lenght - supported tube: 3/8" - 5/8" ID/OD (roughly equalls 10/16mm ID-OD) - outer diameter of a fitting: 22mm - installed height: 15.6mm - compatible tubing: PVC, EPDM, Norprene, silicone, most types of flexible tubeROHS Compliant!