Information on GNC in Slippery Rock, PA 16057 Outlet Note Regular Brands GNC Pennsylvania Slippery Rock 329902 Rating 4.7 based on 97 votes Address 221 Grove City Road Slippery Rock, PA 16057 Phone Hours may vary in different stores. For accurate hours, please contact each store directly. Suite643 Hours may vary in different stores. For accurate hours, please contact each store directly. Nearby GNC Outlet GNC Outlet - Beaver Falls GNC Outlet - Aliquippa GNC Outlet - Bethel Park GNC Outlet - Bethel Park People Also Viewed