This is a NYCS (New York Central) Railroad switch lock with chain, steel, made by Adlake, patent date 1936. There is no key.
The lock body is heavy steel, about 3-1/2" high, total weight about 13 ounces. The drop (keyhole cover) has the maker's name- Adlake- in raised script, an older style, and it still has a very strong return spring. The backside of the lock body is stamped "NYCS" with a long patent number underneath that was issued in 1936. The shackle is steel, and on the front side has 3 stamps-a diamond with a letter or number in it, can't read; an oval with a letter-like stamp hard to read, and a plain stamped "12" near the hinge end. This padlock does come with what appears to be an original chain, but there is no key.
This lock came from a RR employee's collection- he is from northern Indiana, where many lines converge going to and from Chicago..
CONDITION- The steel body is rather evenly dark, but not rough from rust. The shackle has had some rust making the stamps on it hard to read- it is clean now. There is a slight dent or rub on the back side of the body near the bottom. The chain is still quite smooth, little rust. Because of weight I cannot ship this first class package mail but must send it priority mail; postage is offered at cost..
Check my other railroad keys and locks offered on my Ruby Lane site!