The Ultimate Solar Helmet is an armor item added by GraviSuite and worn in the head slot. It is a combination of the Ultimate Hybrid Solar Panel and the Quantum Helmet; however, it does not provide protection against malicious effects, the headlamp function, the food replenishing function, nor the air replenishing function that the Quantum Helmet does, as the solar panel is taking up the space of these modules. It stores 1 million EU, generates 512 EU/t during the day, 64 EU/t during the night, and 0 EU/t if the sky is not visible, just as the Ultimate Hybrid Solar Panel does. These values can be changed in the config for GraviSuite. As the Ultimate Solar Helmet requires both a Quantum Helmet and an Ultimate Hybrid Solar Panel, it is a very expensive armor piece.
The Ultimate Solar Helmet can charge any armor, tool or item in use or present in the inventory, such as the Mining Drill, Chainsaw, BatPack, RE-Battery, etc. It prioritizes charging armor slots, and then charges tools and items in the inventory. A better way of charging tools would be to have a GraviChestPlate or Ultimate Lappack equipped to receive power from the Ultimate Solar Helmet and transfer it to the electric tools.