Hours Of Operations GNC California Clayton GNC Hours of Operation and Locations in Clayton, CA 4.9 - 150 votes 1 Locations in Clayton GNC Hours Category: Beauty & Health GNC - Clayton, CA 94517 5435h Clayton Road(925) 672-6854 View Store Details Explore ClaytonView More Apparel CoachNew York Sports VansSnap FitnessAll Sports Recommend For You Cotton on Bally Total Fitness Eastern Mountain Sports Trader Joe's The Athlete's Foot Diane's Beachwear Bottega Veneta Hanna Andersson Louis Vuitton Sportsman's Warehouse