SpaBoss pH Plus easily raises pH levels in spas and hot tubs that are too low below the recommended safe range of 7.2 to 7.6. If levels are too low, your hot tub water can become acidic and other nasty side effects can happen.
Thumbscrew 1/4 - 20 x 1.75 inch. These are used to secure your corner skirting pieces on your spa in place. This part is the longer of the two thumb-screws available.