The fobs pictured that use the smaller CR1220 battery are the "new" type being manufactured for Xpart as a replacement
for the 3TXA/3TXB/17TN and is supplied under part number YWX101220A.
These usually "program in" with only 2-3 presses of the button rather than the usual 8 presses.
The new design fob will only be manufactured as 433MHz, 315MHz is now discontinued and no longer available.
Another piece of info, the 3TXC fob variant was a Land Rover item. It will program to the 5AS but it does not have the components
fitted to make use of the "friendly mobilisation" feature where the immobiliser self-cancels when the ignition is turned to
position II. This fob was originally supplied with late Land Rover Freelander 1 that didn't require this feature after the introduction
of the BMW EWS immobiliser on these vehicles.