procurement of spares for g r power switchgear ltd . make 420 kv isolator installed at 400kv switchyard at 2x660 mw , sstpp , mppgcl , dongalia , one complete pole of 420kv 2500amps hdb isolator with one earth switch alog with operating mechanism for main switch and for earth switch but without supporting structure , without support insulators and without terminal connectors , copper contact finger fo male and female contacts- per pole . , limit switches , rotary bearig for isolator ( 3 nos . of each type ) , terminal pad , motor operating mechanism boxes for main switch and for earth switch ( for followers drives ) , auxiliary switches for 10 no+ 10nc contacts