Keystone Building Products, Inc. P.O. Box 423 Rt. 522 South Selinsgrove, PA 17870 (570) 374-7565 (570) 374-3866/FAX Contacts: Bruce M. Witkop, President - brucew96@ptd.net David Hostetter, Marketing Manager Gene Gillaspy, Modular Sales Manager Specialization: Service to Manufactured housing industry. Quality is key at KBP. Vendor & Customer “Building Solutions” together. Quality name brand products. Certainteed Siding, Variform Siding, Certainteed shingles, IKO shingles, Mid Continent Cabinetry, Jeld-Wen Interior & Exterior doors, Perma-door, Superseal Windows, Prefinished Mouldings, Berger Aluminum, and introduing Peachtree Windows & Doors.