Neewer 3 Piece 7-14-28mm Macro Extension Tube Set for M42 Screw Mount Camera Lens, Extreme Close-ups This Macro Extension Tube is used by attaching between camera body and M42 screw mount lens This extension tube does not affect image quality as there is no optics inside. In comparison, close-up filters are often blamed for degrading image quality. This extension tube is consists of 5 parts Camera Body Mount Adapter,Lens Mount Adapter,7mm tube (Tube 1),14mm tube (Tube 2),28mm tube (Tube 3) The 3 tubes of differnet lenghts can be used individually or in any combination to obtain the desired magnification. Used with 50mm header can reach 1:1 magnification.