Gain all the benefits of through-the-lens (TTL) loupes without the expense or delay of customization. TTL Easy Size Loupes are complete with four sets of interchangeable, progressively spaced lenses, each with an integrated, screw-in attachment for the Galilean magnifying loupes included. Simply measure your pupillary distance (PD) with the precision scale included. Select the lens pair that corresponds to your PD and quickly snap those lenses into the frame. Each lens has a threaded receiver for the Galilean magnifying loupes. Install the loupes and you are ready to go—in a matter of minutes. Available in both 2.5X and 3.0X magnification options.