I purchased this on another site and in my haste got the wrong size ring... can anyone use a very secure MCD? This is a Lori's Chastity Tube P/A model. This device was ordered from Lori's a few years ago for around $495 and received after about 6-9 months. Waiting for one of these High Quality Chastity Devices to be custom made takes an excruciatingly long time! This device has been used only a few times. The device's testie/support ring measures 1-3/4" OD with a 1 -1/2 " ID, The tube diameter maesures 1-1/2" inside tube diameter, and 6-8ga P/A piercing. The device comes with 2 locks and keys. Totally secure especially with P/A piercing, absolutely no way of "pulling out". Please feel free to email me any questions concerning the device. Fast shipping as soon as payment is received.