Check it out, and the seller told me these are double-sided:

http://www.ebay.com/itm/Sargent-Greenleaf-Jail-or-Prison-Door-Lock-Cylinder-Key-/251112838708?pt=LH_DefaultDomain_0&hash=item3a777dd634#ht_2145wt_202

lots of em come online all the time vs diminishing demand = cheaper price

Cheers

The guy lied about the locks being double-sided.
I bought one--it was single-sided.

The dealer offered to refund me, but I told him it's unnecessary. This is still a very nice piece for the price and suits my needs.

Steve does it have Sargent & /or Greenleaf name anywhere, i have two that are similar, working are a little different and they are not marked and no key ,but the key appears to be close to your type, so i'm trying to find out if they might be S&G's

also pepe --did yale ever make them, thats who the seller told me he thought they were made by?

LK D~D

The key is stamped as Sargent & Greenleaf.