Dual Manufacturing Co., Inc. has produced testing sieves and related products and has become the industry leader and has always been known to product the highest quality products without sacrifice. Dual Mfg is the only sieve manufacturer that is still owned/operated by the founding family, all others have either merged or been bought out by financial institutions. In addition, Dual Mfg does not subcontract any part of the manufacturing process. We keep all aspects of manufacturing inside the organization. This is one of the reasons why our quality has never been tarnished. Dual Manufacturing Co uses only the highest quality alloys in their manufacturing process all of which are certified by the manufacturer as complying with stringent metallurgical standards. Our commitment to quality and service has been the cornerstone of our company since it began in 1942.