The required spacing can be achieved by combining several extenders of differing lengths,you can use 1 piece, 2 pieces , 3 pieces or 4 pieces of the extension rings as you like.
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.
Use this extension tube for getting the correct image scale or the exact spacing required for reducers or field flatteners.
Male thread - M42*0.75. Female thread - M42*0.75,eliminates a range of focusing problems.
