That is a Pentair Replacement Light Pilot Screw with Captive Gum Washer. Used with various Pentair pool lights such as the Amerquartz.
Pilot screw replacement
Fits Pentair IntelliBrite 5g Color and White LED pool lights
Also fits Pentair SAm Spectrum Amerlite, SAL Spectrum Aqualight, Amerlite and AmerQuartz pool/spa lights
Also compatible with Pentair Sta-Rite Sunbrite II and Sunglow II pool/spa lights
Made of stainless steel and includes captive gum washer; Measures 4-inch length by-inch height by 3-inch width
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Pentair 619355 Stainless Steel Pilot Screw with Captive Gum Washer
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Description Warranty Information Pentair Pool Products | SCW SS PILOT | 619355 This product has a 1 year warranty from the manufacturer
Pentair Pool Products | SCW SS PILOT | 619355