ACOPOWER 150Wh Portable Solar Generator

I own and tested numerous chargers including Goal Zero products. Goal Zero is pricy but offers outstanding customer service, safety, recall assistance, certified and reliable products. Anker is my other go-to best product. Was excited to see this alternative product here on Amazon at a reasonable price. Pros: Very Portable. Lithium-Ion battery. Charges well with HQRP 40 Watt solar panel. Vehicle charged ok. Cell phone charging OK. MC-4 cable included. The company is good about notifying customers. Cons: As other reviewers stated, no solar charging instructions. Hissing sound as sunlight changes (the company did say this would happen) but should be fixable to alleviate any user worry about unattended charging. Update: 4/15/2019-Still going strong. Great for power outages. I use it primarily to recharge Anker/other power-packs. Also used twice during photo shoots to power two low wattage LED umbrella lights in locations with poor overhead light and no outlets. Again really portable, solar charged device. (I replaced weathered wires from my old HQRP solar panel connected this power pack with certified heavy duty MC4 power cables, just for my own peace of mind).