This is from the specification sheet for the unit from AP:

40m - max. Depth with air diluent.
100m - max. Depth at which all rebreather parameters are proven: CO2 endurance, O2 control and work of breathing.
100m - the limit of the CE approval.
110m - max. Depth at which the work of breathing has been tested using Trimix diluent.
150m - max. Depth at which the work of breathing has been tested with an Heliox diluent.
160m - Depth at which all components are pressure tested during type approval (not during production).

WARNING! Diving deeper than 100m carries the following additional risks.

Deeper than 100m: CO2 endurance unknown.
Deeper than 100m: Onboard decompression invalid.
Deeper than 110m: Work of breathing with a Trimix diluent unknown.
Deeper than 130m: Depth gauge inaccurate.
Deeper than 150m: Work of breathing with an Heliox diluent unknown.
Deeper than 160m: Structural integrity of components unknown - the air cavity within the buzzer will implode eventually, and other components may fail.