Compatible with the following current Kowa System-S spotting scopes: TSN 663M, 664M, TSN-601, 602, TSN-82SV. The digiscoping adapter is suitable for DSLR as well as compact and mirrorless system cameras. Digiscoping with a Kowa spotting scope has never been easier. The eyepiece is unscrewed from the scope body. The inner ring of the TSN-PA8 adapter connects directly to the accessory thread on the scope body. Then, the eyepiece is reattached to the scope, and the outer ring of the TSN-PA8 adapter can be slid over the eyepiece and secured with the knurled screw. It has been designed for use in combination with the TSE-Z9B eyepiece, allowing the entire zoom range to be utilized even when digiscoping, achieving very high focal lengths. This adapter can also be used with many older Kowa spotting scope models that have been on the market for decades.