Rapture's U-Probe 3-1/4 Inch Smooth Shaft Urethral Plug has a smooth shaft and a very gradual taper that offers the beginner in urethral stimulation a gentle and safe introduction. The shaft of this plug measures only 3-1/4 inches (8.25cm) long. It features a bent shaft end for easy insertion, control and safety. The end of the plug starts at a mere 3/16 inch (5mm) diameter and tapers up to maximum diameter of 5/16 (8mm). The shaft bent end is only 1/8 (4mm) in diameter. The plug is made of polished surgical stainless steel for maximum safety and hygiene. It is packaged in a plastic case suitable for storage.