Resound hearing aids: how to find out if it is a 5, 7 or 9 series

Hearing Aids
#1

I am searching for offers of used Resound hearing aids on various websites. In many cases, the sellers do not know what type of hearing aid they are offering. From the pictures it is easy to distinguish between the model such as as 60, 61, 67, 88 etc. But how to find out if it is a 5, 7 or 9 series?

Thanks
Piet

#2

Open the battery door and look inside. You’ll likely need a light and possibly a magnifying glass.

Looking inside one of my Linx2s, it says “LS962-DRW”. The 9 tells you it’s a level 9 and the 2 tells you it uses a size 13 battery.

The second line is the serial number.