The MeoPix iScoping adapter is a revolutionary new tool for anyone wanting to capture long range images. The MeoPix iScoping adapter slips over the spotting scope or binocular eyepiece - cradling your iPhone 4/4s in perfect alignment to the optic - allowing your iPhone to capture amazing long distance images. Fits 49mm eyepiece. Works with: Cabela's Alpha, Vortex Viper, Meopta Meostar S2 HD, Steiner Night Hunter & Predator Xtreme, and Vortex Kaibab.