Note: The color of the product we ship is the color in the first picture, and the specification and quantity are shipped according to the quantity and specification described in the title. If you need to change the color or style, you need to contact us within 12 hours after placing the order. Our product Product Features: 1.Every product has a unique Manufacturing Part Number label on the inner package that proves it has been qualified,which include Part Number,Model Number and inspection date information 2.If you have any questions about the item,please provide us the Manufacturing Part Number for checking,your profits will be guaranteed.3.The piston set of the air compressor 42 is made of metal. Size: Piston diameter 42MM, height 36MM, aperture 12MM, piston ring oil ring thickness 3MM, gas ring thickness 2MM, piston pin length 34MM, diameter 12MM circlip: 13MM.4.Suitable for air compressors.5.The accessories include a piston, a piston ring oil ring, two gas rings, a piston pin and two circlips.Specifications:Product material:MetalColor:Silver and Black name: BQLZRSize:4.2 x 3.6cm or 1.65 x 1.42inch(D x H)Piston diameter 42MM, height 36MM, aperture 12MM, piston ring oil ring thickness 3MM, gas ring thickness 2MM, piston pin length 34MM, diameter 12MM circlip: 13MM.Weight:83gPackage include:1 x Piston1 x Piston Oil Ring2 x Gas Rings1 x Piston Pin2 x Circlips Note: Because the model and display effect of the monitor may be different, there may be slight differences in color, and the size is manually measured, there may be an error of 1-2cm, please understand.