What's in the box:

Andoer M52-M42(17-31) 17mm-31mm M52 to M42 Mount Camera Lens Adapter Ring Macro Extension Tube Helicoid Lens Focusing Adapter Ring for Macro Photography (Standard)

Features
[Broad Compatibility] Suitable for M52 mount lens and M42 mount adapter ring, providing a focusing system for camera.
[Focus Length] Can be adjusted from 17mm to 31mm, support manual focusing, satisfying your various needs, flexible and convenient to use.
[Macro Extension Tube] Can be used as an old lens and macro extension tube, perfect for macro photography, digital camera photography, and more, easy to install and use.
[Premium Aluminum Alloy Construction] Made from high-quality aluminum alloy with advanced anodic oxidation technique, sturdy and durable.
[Compact Size and Light Weight] Max. 7cm diameter and weights only 99g, convenient for storage and carrying.

Specifications
Brand: Andoer
Model: M52-M42(17-31)
Color: Black
Material: Aluminum alloy
Product Size: 7 * 7 * 2.2cm/ 2.7 * 2.7 * 0.86inch
Product Weight: 99g/ 3.4oz
Package Size: 7.6 * 7.6 * 3.3cm/ 2.9 * 2.9 * 1.2inch
Package Weight: 109g/ 3.8oz

Note:
Only the camera lens adapter ring is included.

Package List
1 * Adapter Ring