Most A.C. chippers who have a copy of my book know about the letter "i" variations that are found on these Harrah's CIC chips. The original chips were of the normal "i" letters while the later re-order chips had what is described in my catalog as the "mini-i" letters. The HAR-5b ... then back up chip to the original series ... is of the normal "i". Keep a sharp lookout for the mini "i" red/white chips ... which may or may not exist.