These panels come to us from Voltaic Systems, makers of fine solar-powered bags and packs. These are waterproof, scratch-resistant, and UV-resistant, and they use four high-efficiency monocrystalline SunPower cells with 22+% efficiency (praise the sun!). The panel is made of 4 cells with a nominal voltage of 0.5V each, so we call this a "2V" panel

• They output a nominal 2V at 150 mA peak via two solder-able pads on the back. The panel is constructed with ETFE (Ethylene Tetrafluoroethylene), making it extremely durable and resistant to environmental elements, a superior upgrade to PET or laminate solar panel construction. They can easily stand up to typical outdoor use, including being dropped and leaned on. 
• Unlike the larger panels, these don't come with a connector. Instead, there are two pads on the back. To connect, we recommend soldering two wires and attaching a 2.1mm terminal block. (Or you can cut off the alligator clips from a 2.1mm-to-clip adapter)
• Note that these will not work with our solar charger boards (they expect 5.5 or 6V panels) but there may be projects that can either benefit from a smaller voltage panel, such as power harvesting circuits. Or, you could connect 3 of these in series to get nominal 6V output.

Specifications:

• Features
• Waterproof (IP67)
• UV resistant (5-7 year life)
• Durable and lightweight
• High-efficiency monocrystalline cells: 22+%
• 2x Solder Pads
• Size and Weight
• 52 x 52 x 3.1mm
• 8.2 grams
• Construction
• Matte ETFE coating
• 1.5mm double-sided PCB
• Warranty:
• 2-year warranty on solar panels
• For more warranty information, see the warranty guide
• Product Dimensions: 52.0mm x 52.0mm x 2.7mm / 2.0" x 2.0" x 0.1"
• Product Weight: 11.0g / 0.4oz

Documentations:

• Specification Sheet
• Diagram
• Datasheet

Package Includes:

• 1 x Adafruit 5853 2V 0.3W Mini Solar Panel - ETFE - Voltaic P121