plastics cover:           Specification                 L                    W                     H           NTSM-4ways 150 225 20 NTSM-6ways 195 225 20 NTSM-8ways 230 225 20 NTSM-12ways 300 225 20 NTSM-18ways 425 225 20 NTSM-24ways 300 345 20     plastics base:   Specification          L                    W                   H          NTSM-4ways 112 200 66 NTSM-6ways 150 200 66 NTSM-8ways 184 200 66 NTSM-12ways 256 200 66 NTSM-18ways 365 220 76 NTSM-24ways 257 310 76