This 4th generation Baader Hyperion 8-24mm
Click-stop Zoom is smaller (55mm wide) and lighter (290 grams) than its
predecessor (the Mk-III model was 80 grams heavier). This makes it an especially
good choice for use with binoviewers.
It has an additional 4 millimeter 'back-focus' so is more compatible with
spotting scopes that accept 1.25" e more