They appear to be regular sex shop silicone cock rings. You can slip them on before or after you use the
Bathmate. Cock rings are intended to retain the engorgement resulting from the
Bathmate session. The description says you can also use them to improve your erection even when not using the
Bathmate. They come with tiny vibrators attached to improve stimulation.
You can probably get similar products from reliable sex shops at a lower price.