Narrow/wide chainring will grip the chain perfectly, prevent chain drops.7075 aluminum alloy T651 heating treatment. Light weight but also high strength.Precision machining and anodic oxidation electroplating, keep surface smooth, bright color, not faded and corrosion resistance. 4mm chainring thickness to ensure no flexing.We will ship from real UK warehouses,dispatch in 0-2 day,fast and efficient shopping experience, as well as brand quality assurance for you. Chainring Description: Brand:DECKAS Color:Black,Red Material: 7075-T6 Aluminum alloy BCD: 104BCD Teeth: 32/34/36/38/40/42/44/46T/48T/50T/52T Weight: 51g/34t, 151g/52t (different size,different weight) Thickness:4mm Positive teeth:3.7mm Negative teeth:1.9mm Compatible with: All 8/9/10/.