This offer/listing is for One (1) ONLY, Believed to be a now Rare Found Vintage New Old Stock OEM Genuine Mercedes-Benz/ATE Factory Single Circuit Brake Master (23.81mm bore) Rebuild/Sealing Kit with single piston and comes without the check valve, grab it NOW while you can Still Find it! Quality made in Western Germany not Asian like the latest re-popped MB parts. Applications are believed to be for many later 1950's and early 1960's Heckflosse 190c, 190Dc, 220b and 220Sb without power brake booster Model Vehicles! Related part #s are A 001 586 20 43, 0015862043 and 0370-0123. Box could have minor Vintage Surface Wear and/or from over 35 years of dealership storage! Stored in Climate Controlled Condition for many years of dry parts room storage! Please study photos carefully as you will be receiving this exact item. Also check with club or dealership specs and your measurements, ask any questions and double check/compare your actual needed part# to our listing prior to bidding. All NOS parts are subject to some possible deterioration, oxidation and shelf-ware from age and long term storage. For this reason we can offer NO Warranty on New Old Stock Parts!