Lot of 5 Large Neuter Bow SC1 Key Blanks (5 pin, C keyway) stamped "Do Not Duplicate".  Neuter bow key blanks have no identifying numbers indicating the type of lock, which makes it harder for inexperienced folks to duplicate.  "Do Not Duplicate" is clearly stamped on the head of the key, making it less likely that it will be ignored or overlooked.  Locksmiths and most reputable hardware stores will refuse to make copies of these marked keys.  It will not prevent all duplication, including the self serve key kiosks, but many people will be hesitant to try getting them cut.  The blanks work on Schlage F series, B series, J series and any Schlage commercial locks using 5 pin C keyway cylinders.  They will also work on many higher end imports using Schlage keyway cylinders.  If you are unsure if these are the correct keys for you, please email me a picture of your key before ordering.