Copper Test Strips for Pool Water: 25 Counts Pool Copper Test Kit for Testing Range 0-2 ppm Copper in Swimming Pool Hot-Tub Spa - Pool Metal Test Kit for Above-Ground and Inground Pool Testing Copper auspowers_batchthree the blue light will light

the blue light will light up and flash

Also fits Shimano disc brake lockrings

As seen on ABC

Position the bit in the Predrilled Hole

Copper Test Strips for Pool Water: 25 Counts Pool Copper Test Kit for Testing Range 0-2 ppm Copper in Swimming Pool Hot-Tub Spa - Pool Metal Test Kit for Above-Ground and Inground Pool Testing Copper auspowers_batchthree the blue light will lightCopper Test Strips for Pool Water: 25 Counts Pool Copper Test Kit for Testing Range 0 2 ppm Copper in Swimming Pool Hot Tub Spa Pool Metal Test Kit for Above Ground and Inground Pool Testing Copper Product Features Why You Should Test for Copper in Your Pool: Copper can sneak into your pool through source water, copper based treatments, and corrosion. High copper levels can disrupt your pool's chemical balance, damage equipment, and cause skin and eye