Use this extension tube for getting the correct image scale or the exact spacing required for reducers or field flatteners
The required spacing can be achieved by combining several extenders of differing lengths;you can use 1 piece;2 pieces;3 pieces of the extension rings as you like
Male thread M42*0.75;Female thread M42*0.7;eliminates a range of focusing problems
The extension tube has a T2 interior thread and a T2 exterior thread for elegantly solving spacing problems in astrophotography
All metal construction and anodizing aluminium process;durable for long time use