Doc Johnson Vac-U-Lock system allows lots of interesting fun toys that are attachable to your harness. Fun stuff to add to your Doc Johnson Vac-U-Lock harness. Doc Johnson Vac-U-Lock dongs offers a large variety of incredible fun to use on your partner and while doing so for yourself. Wow! These Doc Johnson Vac-U-Lock harnesses provide a variety that are unbelievable you can really get it on with these babies. All I can say is try one or more of these. Some are for auto satisfaction, but can convert to be used to bring joy to your partner. Large variety of strap on devices especially made for the ladies. They will hold your toy in place safely. Keep a few different ones on hand, like the one that comes with the penis or insert hole for your other toys. Then go wild doing your best to please yourself and your partner.