The TPL Birdy is produced by https://tplsystemes.com and was originally designed for usage in French fire departments, therefore they are waterproof (IP67) and robust.
The current version is the Birdy WPs r2 with 128 RICs, each with 4 subaddresses. The older model has only 8 RICs, but the battery lasts with that model for months. Disadvantage of the birdy: Storage for only 20 Messages (each 256 characters).
The RICs cannot be handprogrammed on the pager, but switched off/on „in the field“.
There is no programming cable available, but the charging station can be modified for programming.