For cruising boaters, RV travelers, or off-the-grid application, these rigid monocrystalline panels are efficient and affordable.High-efficiency rigid panels can keep your boats battery banks charged and minimize engine run time.Efficient technology: These panels use the most efficient German-made monocrystalline solar technology on the market today. This 165-watt panel has an 17.2 percent efficiency rating.Simple and rugged: Equipped with heavy-duty aluminum frames for strong weather resistance and permanent mounting. Theyre simple to install, equipped with easy to use plug-and-play connectors.Scalable for expanding to build large arrays: Modular design is ideal for expandable solar systems.Blocking diode: Includes built-in blocking diode to prevent reverse flow of electricity.Power generation warranty: Manufacturers 25-year power generation warranty that the panel will produce 80 percent of rated powerRequires a charge controller: Nature Power panels over 12 watts require a charge controller (typically mounted within 5' of the battery bank). The 28-Amp Nature Power controller (sold separately) is recommended.Maximum Output: 9.43A (at 17.5V open circuit voltage)Weight: 24.6lb.What's in the Box165 Watt Monocrystalline Solar Panel with Aluminum Frame11 feet of cableBattery Clamps4 x Z-brackets with screwsOwner's Manual