Seamless Metal O-Ring 3 Pack 1.5 inches, 1.75 inches and 2 inches from Sportsheets. These O-rings can be used with any flared base dildos on an interchangeable O-Ring harness. Use with Sportsheets harnesses including Plus Strap On, Vibrating Black, Purple Velvet Strap On, Vibrating Black Strap On,...