The Konus 2x Barlow Lens is an economical option to increase the magnification range of your telescope by doubling the power of the eyepiece in use. This model inserts into 1.25" focusers and accepts 1.25" eyepieces, but also has an outer threading so that you can attach an SLR camera and photograph through the telescope/barlow/eyepiece combination. Your camera's specific T-mount is required.