VIPER® HD RETICLE EYEPIECEDescription Want to be a better shot caller? Put a Viper Reticle Eyepiece on your Viper HD 85mm spotting scope and it becomes the perfect optical measuring stick for making spotter to shooter communication fast and easy. A fixed magnification of 33. 5x gives you all the power you need, and a diopter ring and the ability to rotate the reticle to level it with the horizon line lets you customize your view.