Check the listing for details. Waterproof DC/DC Converter 12V Step down to 3V 3A 15W Power Supply Module. Condition: New. Listed at 13.99 USD. Features:All epoxy sealed containers with Waterproof Housing;Light compact, convenient to use and transport;Non-isolatedHigh efficiency:>96%;Reliable, low heat dissipation max. 40 ℃;With overload / over-current / over / low voltage protection, stable performance.Auto recoverySpecifications:Input range: 8~23vOutput voltage:3VOutput current/power:3AEfficiency: ＞96%Weight: 30gSize(LxWxH): 26×36×21(mm)Cable length: 100mm Package included:1 x DC12v to 3v 3A 15W Converter - Many customers ask if they can ship their products in a paper envelope. Unfortunately, we cannot do that because merchandise needs extra protection, and USPS does not provide a tracking number for this type of service.- The shipping service we offer is First-Class Package Service, which is a domestic mail service offered by USPS. It is designed for mailing lightweight packages that weigh up to 15.99 ounces and offers delivery in 1-5 business days. It includes a tracking number, allowing customers to track their packages. USPS prices start at $4.75, but we don't have any control over shipping prices.