Bisley Scope Maximiser
The scope enhancer, or maximiser, is a simple idea that can make a big difference. The moulded rubber shroud is a push fit, onto the end of the Ocular (rear) lens of the scope, with the idea being that that rubber shroud almost seals against the face, eliminating any backlight from entering the rear of the scope. This helps to accentuate the image, creating a bright, crisp sight picture, sharply contrasting with the black surround. Any chance of distraction caused by wind, dust or even movement is also minimized. In effect by eliminating all other light sources, your eye will be forced to adjust, and in so doing, make the maximum use of the light in the scope. Initially, the shroud should be able to twist forward or back along the scope body, until the correct eye relief is achieved. At this point, the shooters eye should be pressed comfortably up to the lip of the shroud.
The Maximiser from Bisley has just the right amount of flexibility in the rubber, so should fit most scopes with some gentle coaxing. In other words, that pleasingly flexible body is intended to be a one-size-fits-all design. The initial diameter is 40mm, but with plenty of flex, Bisley claim it will fit 98% of all scopes out there!