The Zefal Spring bottle cage is constructed from thermoplastic resin to ensure it is flexible to fit a variety of water bottle shapes. The Spring bottle cage weighs just 46g at an exceptional price and is available in a subtle black or crisp white version. Review | 4.5 / 5 "Cheap, light, effective and stylish, all for just a fiver"Bikeradar Key Features: Fits all standard  cycling water bottles: Diameter 73mm, Capacity 500ml to 1,000mlFlexible design: Adapts to slight differences in bottle shapeUniversal two bolt frame fit: Attaches to any bike frame with standard bottle cage mounts (bolts not supplied) Multi position: Suitable for attachment to downtube and/or seat tubeMaterial: Thermoplastic resinWeight: 46gColour: Black, White