Aqua Optics Dive Mask Magnifiers (1 Pair) Optical-quality glass lens kit with glue install in any scuba or snorkel mask with flat lenses. Removable and reusable. Won't accidentally wash out of your mask. Each package includes two semi-circular lenses, installation glue, and complete instructions. Installation takes minutes, and the glue sets completely in 6 hours. Mask not included.