The Kowa TSN-VA2B is a digiscoping adapter which isn't used together with an eyepiece-it is used instead of an eyepiece, and projects a long, consistent beam of collimated light for use by digital point and shoot or video cameras. The TSN-VA2B has built-in 14x magnification with the TSN-88* or TSN-77* series spotting scopes, and 12x with the TSN-66*/TSN-60* scopes. It attaches directly to the 88/77mm scopes like an eyepiece, but the 66mm/60mm scopes will require the TSN-CR3 adapter between scope and eyepiece. The TSN-VA2B is a revision to the now-discontinued TSN-VA2, with superior optics but otherwise much the same function. The extremely-long eye relief of 100mm allows nearly any camera to work without vignetting; you must attach a DA series adapter ring to your camera's filter threads and away you go. While any digital non-SLR camera with 28-72mm filter threads works, the VA2B was designed around the exceptional digiscoping performance of Casio's Exilim Pro EX-F1, and even have a dedicated support bracket (TSN-PS2) for the combination.
