Designed for fans of hands-free play, the unique curved base of the Silicone Noir Rockers feature embedded 2mm inputs that allow you to sit on, rock and grind against the e-stim butt plug during wear. The Silicone Noir Rocker Butt Plug - Medium sits in the middle of this range and is ideal for anyone experienced in anal play that's graduating from one of our smaller designs. Created from 100% platinum-cured black silicone, the tapered shape assists insertion and the subtle ridged texture enhances sensation during wear. Seamless bi-polar contacts in the shaft transmit sensation from an ElectraStim stimulator (sold separately) making your anal pleasure zones tingle and the muscles pleasurably throb in time with the stimulation pattern. Insertable Length: 115mm / 4.5 inches. Max Diameter: 39mm / 1.5 inches. Max Circumference: 125mm / 4.9 inches. Connection: 2mm. Weight: 172g. Materials: Platinum cured medical grade silicone. Number of Poles: 2 (bi-polar).