This is a very sophisticated aluminum bumper jack marked ALCOA 4, but I thought was  English, that is missing the base. . I have been advised by aomeone who has one with a base, that base is marled Narragansett Manufacturing Company. That company made lathes and precision tools .It seems to have a hydraulic cylinder with a bleed or release. I do Not know what it fits, but suspect due to its' high quality, it may be suitable for  an older Rolls Royce, Land Rover, OR, I once had a 1938 Alvis Speed 25 in my shop, that had much aluminum; perhaps it left without its' jack. Any advice to identify is appreciated. The numbers given are hard to read, and may be casting numbers of the various parts.It is missing the base. Due to the high quality, I would suggest machining one of aluminum would be justified, though one could probably be made of. steel.Perhaps using an appropriate front wheel hub and brake drum, reinforced with a steel disk, if you are creative.?.Please inquire  1 954 JAGUARS  or  1 954 JAGPART. PleaseLook in my eBay store, Old English Motor Company, I have a thousand original parts like this,1950-1994; organized in 20 categories including  Rover  Parts..   Click on the one you want. . There are  many thousands more, for all English cars; in my warehouse. I have been compulsively hoarding and running a restoration shop for 30 years, and saved everything. If you don't see what you need, please ASK. I will put it in the store for you, with photos...SHIPPING  . in the US is FedEx out of the US is Priority Mail but is an Estimate; Please give me your address  for exact ovberseas  shipping cost . Some countries now require ..I ship worldwide.Thank you, James Dean,  thejaguru. ..NOTE, I am now located in  Sebring the Heart of Old Florida...