For SVBONY SA404 is designed for telescope with M48 external thread, SA404 is used to convert M48 external thread to M42 external thread, then people can use Canon/Nikon/Sony camera with camera adapter. It also fits 1.25 inch astronomical telescope eyepiece.<br> If you have any other scope with M48 external thread, SV404 also fits your scope.<br> Model: SA404<br> Interface: M48 internal thread to M42 external thread with 12.5 inch hole<br> Primary mirror interface: M48x0.75<br> Accuracy: 0.1mm<br> Height: 31.5mm<br> Colour:Black<br> Material:aluminum alloy<br> Package Contents:<br> 1 * M48 Female to M42 Male Adapter<br> Only the above package content, other products are not included.<br> Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.