The Ultra Lite peep weighs only 7.5 grains – approximately 25% lighter than the original Super Peep housing. The peep opening is 3/16". The Ultra Lite Peep is designed to accept all of the Super Peep 1/8" apertures, clarifiers, and verifiers. Use of our dual aperture wrench (210078) is recommended for insertion of optional apertures, verifiers, and clarifiers.