BATANGHARI TEBING PERKASA (SEF), PT North Sumatera Rubber Product, SIR 10, SIR 20, Wati, Des. H. Asril Sultan Amir, Ak. btpratama@nusa.net.id (62-621) 21496, 22848 (62-621) 21585 Jl. Prof. M. Yamin, SH. Tebing Tinggi