To connect tubing of different internal diameters. Riffled limbs provide secure attachment. Suitable for tubing with internal diameters: 4 to 7mm and 7 to 12mm.Nominal OD: 4/6/8 & 10/12mmCrest OD: max/min 3.7/8.2 7.0/11.8mmBore: 1.6/4.6mmMaterial: Polypropylene