Product Name: for Rolling Unreeling Key Type Air Shaft Drum Model NO.: 3" V. S 6" Material: Aluminium Coatings: Oxidize or Chromeplate Production Time: 10-15 Days After Received The Payment Trademark: weizheng Transport Package: Paper Tube or Crate. Specification: 100mm-2500mm Origin: Dongguan, Guangdong, China (Mainland) HS Code: 8449009000 Product Description SpecificationsAir shaft drum:1. High quality with low price2. Excellent performance3. High precision shaft4. Quick deliver5. OEMIntroduction:1. Air cover has key type andboardtype, air cover also called air drum.2. Usage: Set outside the 3 inches air shaft, can achieve the six inches efficient.3. Inner bore Ø 76mm, outside diameter is 150mm, the length is according to the customers' request.4. Adopt the high quality aluminum alloy hard oxidize, the surface color is tawny, use convenient.5. After gassing it is equal to 6 inches air shaft, outside diameter can reach 155-158mm6. The surface of key bar length is 100mm, width is 8mm7. The outside of air drum surface, which part bulge ia made by rubber, having been produced with the design being finalized, we have stock. Total length ID 190mm.Note: The length of the air cover is determined by the customers' needs.The following picture is key type:Performance and advantages: Air shaft in practical applications, it has advantages of convenient operation, quick, without damage rolls etc.Product usage: It is widely used in printing, cutting, coating, compounding and other machineries' releasing and winding scroll.