The Bose L1 Pro range initially consists of three to four systems, depending on the subwoofer configuration.

Bose have a detailed comparison chart available here.

Here are the key differences at a glance:

Pro8

Volume: 112 dB (cont.) 118 dB (peak)
Power: 60w main system, 240w subwoofer
Low frequency: 45Hz
Weight: 18kg

Pro16

Volume: 118 dB (cont.) 124 dB (peak)
Power: 250w main system, 1000w subwoofer
Low frequency: 42Hz
Weight: 24.8kg

Pro32 with Sub1

Volume: 117 dB (cont.) 123 dB (peak)
Power: 480w main system, 480w subwoofer
Low frequency: 40Hz
Weight: 13kg (base and array) + 16.1kg (Sub1)

Pro32 with Sub2

Volume: 122 dB (cont.) 128 dB (peak)
Power: 480w main system, 480w subwoofer
Low frequency: 37Hz
Weight: 13kg (base and array) + 23.4kg (Sub2)