Communication between 2 devices is governed by the capability of the lower power device. The maximum output power and expected range of each Bluetooth class range can be found in the table below:

Class	Maximum Output Power	Theoretical Range
1	100mW / 20dBm	100 Meters
2	2.5mW / 4dBm	10 Meters
3	1mW / 0dBm	10 Centimetres

*The expected ranges assume an unobstructed environment between the two devices*