Starkey Sequel

Hi! I am 25 years old and have a hearing loss that is a little weird. My left ear is non-functional and my right ear I have a mild to severe hearing loss which requires a hearing aid. I have a Starkey Sequel that I got in 1997. Eleven and a half years I have had it! I am currently in the process of getting a digital and am very frustrated. My degree of hearing loss is making it very difficult to program the digital hearing aid. Recently we tried sending my hearing aid in (I borrowed a reconditioned hearing aid for that time frame) and the digital hearing aid into Starkey in the hopes that they would set the digital to mine. Well, it didn’t work. I also believe that Starkey messed with mine because now it isn’t set right. What I need to know is what the lettering on the Starkey Sequel mean. They are as follows

TK
LH
CR
AO

If anyone could help me out that would be great!