The 100mA (0.1A) is a replacement fuse meant to go in your home spa’s PC board. This fuse supplies power to your spa and the rest of its features, so maintaining it is key to the enjoyment of your spa. The slow blow fuse allows more power to flow without overwhelming the circuit.
This is a copper jumper strap normally used with the ground wires in the spa. These are mounted on the back of the pumps connecting the ground wire. Is part of the connections from the heater to the PC Board.