Check the listing for details. 60 Pcs 4mm Tube OD Brass Compression Sleeves Ferrules Fitting Insert Support. Condition: New. Listed at 13.58 USD. This brass compression sleeves ferrule is widely used in pipe connection for hydraulic and pneumatic systems, HVAC, humidifiers, etc., suitable for connecting copper, brass, aluminum, or plastic tubing. And the insert fitting are mainly used to insert into the hose when you are going to use it to connect to a hose but not a pipe.Specification:Color: Brass ToneMaterial: BrassBrass Ferrules Size: 4mmx5.5mmx4.2mm / 0.16 inch x 0.22 inch x 0.17 inch (ID x OD x H)Insert Fitting Hole Size: 1.8mmx4mmx10.6mm / 0.07 inch x 0.16 inch x 0.42 inch (ID x OD x H)Suitable for connecting 4mm hose or pipe. Packing List: 30 Pack x Brass Ferrule, 30 Pack x Insert FittingAdvantage:The brass ferrule insert fittings are made of brass, it is durable and reusable.