Strictgate pledge rings = can't pull out in secret?

I found this devices called Strictgate: http://www.strictgate.com/male-chastity-device/male-chastity-device.asp

It's similar to a Holytrainer by the looks of it. However it comes with these "pledge rings" that you insert into the tube.

Has anyone got experience with them? Do they prevent pull-out? If yes, great! If not, is it possible to secretly put the penis back in (e.g. with stocking method) with the pledge ring in correct position?

It seems to be a similar design to the retainer ring that Lori's devices had, but I find no claims that pull-out and put-back-in is impossible on their website.