1、Application: This adapter tube thread M42 x 0.75 is suitable for T2 mount lens of camera, and T2 adapter ring to mirrorless camera. 2、Height, Diameter Adjustable Valve: The height of eyepiece can be adjusted from 67mm to 80mm. The diameter of eyepiece can be adjusted from 41.5mm to 44.5mm. 3、Scope of Application: Equipped with T2 for EOSM adapter ring, suitable for mirror less camera, which is helpful for visual photography. 4、Aluminum Alloy Material: Made of premium aluminum alloy material, this adapter tube is strong and sturdy, rust and corrosion resistant, ensuring a long life span. 5、Hollow Design: The hollow design of the adapter tube does not affect the focusing wheel, and the adjustment of the focusing handwheel is not affected on both sides.