This collection of four probes for backdoor play is unisex and designed to enhance sensation. By utilizing the body?s natural responses after insertion peridise begins to quiver on its own generating an orgasmic response that can stand alone or enhance a traditional orgasm. Each piece is made from phthalate-free FDA-approved plastic with a nice smooth finish. Widths are 0.87 in. and 0.72 in. Insertable length is 3.25 in.