Features:
Suitable for M42 mount lens without focusing ring.
Can be used as a macro extension tube.
No electronic element, manually controls aperture and focusing.
Aluminum alloy material, CNC precision machining, durable and sturdy.
Easy to install and simple to use.
Specifications:
Material: Aluminum Alloy
Lens Compatibility: M42 screw mount lens
Length:
17mm-31mm/ 25mm-55mm/ 36mm-90mm(optional)
Packing List:
1 * Adapter Ring