Designed specifically to fit their S250 Stedi-Eye stabilized binocular models with detachable eyepieces, this Fraser Optics 10x Eyepiece produces a spacious 4.6°, 240-foot field of view with an image stabilization resolution of 4.7 arcseconds. Standard, nondetachable-eyepiece, Stedi-Eye models have a 14x magnification with a narrower field of view and lower resolution, so being able to utilize these eyepieces improves the precision and increases the view of your binocular when you don't need to reach out as far for observation and identification. Optional 14x eyepieces are available to give you the ability to recreate the standard Stedi-Eye model optimized for long-range use. The eyepiece locks firmly in position on the chassis, so when it is installed the binocular maintains its buoyancy and will still be waterproof and fogproof. This is a single eyepiece; two are required for proper use with the S250 binocular.