Drill holes, push deck lights led in and connect cables. Weatherproof, Ip67 waterproof and rustproof,so this deck lighting can be installed for outdoor decoration, like deck step, stair, staircase,kitchen, stairway, bathroom, pool deck, backyard, walkways, garden, pathway and other outside accent lighting. The led deck lights are equipped with stable and safe copper 2 pin connectors and all glue-filled power adapter, completely insulated and water-proof. Light Size: 1.26" x H0.86". Mount Hole Size: 0.86". Power Adapter Length: 7.87ft/94.44". Distance Between Light to Light: 3.2ft/38.4". DC 12V output(12V power supply transformer included), support Max 20pcs in series.(32mm/1.26")Dia. x (23mm/0.9055")H x (24mm/0.945")Cut out,with 3M/118" power cable from plug to the first light. Max distance between 2 led stair lights is 100cm/39.37". Total length for this outdoor recessed lighting is about 13M/511.81".