Cold-cast copper 2.25U mod keys that have undergone heavy patina.  There is a seal-coat applied over the patina and the keys have been wiped down with a wet cloth, but patina may wear with use or heavy handling.  
 
Please select the particular key you want to receive- the key in the photo is the key you will be shipped.  Keys are either 2.25 R3 (Enter) or 2.25U R4 (L-Shift).