Vac-U-Lock Black Universal Strap On. Take your playtime to the next level. Submission meets action in this dual function ball gag designed for the worlds first fully interchangeable strap on and accessory system. The patented Vac-U-Lock plug end is compatible with any Vac-U-Lock attachment for pleasuring partners, while the soft silicone ball is formed with indentations to accommodate and protect the mouth and teeth during vigorous play