The ATX and STX modular Eyepiece from Swarovski offer unparalleled flexibility coupled with the ATX/STX Modular Objectives (sold separately). Both eyepieces feature twist-out, removable eyecups that offer an extremely wide field of view for any users whether or not they wear eye glasses. The location of the focus ring compliments the modular objectives, allowing one handed operation with any combination of objective/eyepiece. With the increasing popularity of digiscoping, it was pivotal that the ATX/STX eyepieces accept adapters that allow users to capture striking images through the fluoride containing HD lenses. With the Modular eyepieces, the ATX/STX modular spotting scope is the most compact unit available today. Traveling with your spotting scope and digiscoping gear is no longer a hassle with the ATX/STX Modular system. Note: This is the eyepiece only. A Swarovski ATX/STX Modular Objective must be purchased separately for use with the modular eyepiece.