You are bidding on 2 Western Electric type 21W condensers.  These are rated a 1 MFD, 500 VDC.  They are the earliest black examples with paper labels, (mostly missing on one).  One is in fairly nice condition, while the other shows traces of light rust.  They measure roughly 1 3/4 by 1 3/8 inches in cross section, and are 4 inches in length, not counting the terminals. They should be great for your project.  Shipping weight is 2 pounds.  Please see my other auctions for more interesting radio and audio items, and tubes.