that,my boy,is the front brake assembly off an australian assembled datsun 120y,when,due to local content rules,certain parts were sourced in australia.these were from paton brakes(pbr). that's why some 120y's have borg warner diffs.these brakes bolt straight onto 1200 lower control arms,& the caliper is actually from a mitsubishi sigma.can't remember the pad number,but i used these on my 1200's very successfully.they just suffer from uneven pad wear,but throwing a new set of pads always fixed the pad knock off.just another australian peculiarity.