This first aid device is a palm-sized rectangular chunk of ARB with a powerful adhesive along one side. When you want to use it, tear the waxed paper covering off the adhesive and slap it onto a wounded living being. Preparing and applying a Slap Patch is a 3-shot action. Make an Constitution roll for the patient and subtract the Action Result from the patient's Wound Point total. There is no such thing as negative Wound Points and no way to save up healing to apply against future wounds. The patient heals immediately, as the arcanowaves emanating from the ARB patch temporarily reconstitute his DNA for rapid healing.
Each use costs either you or your patiet a single Magic point. If both refuse this cost, there is no healing.
Your supply of Slap Patches are not generally an issue. Your GM may say you are running low on Slap Patches to heighten the suspense, just as he can with any type of gear. In-between sessions you grow new patches using a special kit. It includes a growing vat, tiny crystals of "seed" ARB which grow into the full chunks, a supply of chemical catalyst for the vat (just add some carbohydrate, like blood).