... Test Report for Pole Type 'SP-BH' China Electric Power Research Institute of SGCC, Beijing, P.R. China 220kV Double Circuit Transmission ... Test Report for Pole Type 'SP-BT' China Electric Power Research Institute of SGCC, Beijing, P.R. China 220kV Double Circuit Transmission ... Test Report for Pole Type 'SP-BM' China Electric Power Research Institute of SGCC, Beijing, P.R. China 220kV Double Circuit ...