The Vertex RO/DIs are the most efficient RO/DI systems available.  They maintain a 1:1 waste water ratio, so for preserving water and saving money they are extremely popular.  They come with a booster pump, a computerized TDS meter, auto flush, and auto shutoff.          
EXCLUSIVE FEATURES:
1:1 Pure/Waste water ratio (source water temperature dependant)
Fully-Automated water management
Professional grade digital TDS meter
Easy to view precision Oil-filled pressure gauge
Automatic backflush system prevents TDS creep
High-pressure electronic shut-off for reservoir use
High efficiency booster pump.
TECHNICAL DATA:
Footprint 15" x 8"
Height 18"
GE-100 GPD membrane
5 polypropylene sediment cartridge
carbon block cartridge
High capacity resin DI cartridge
VertexTM HP-100 booster pump
All 1/4" push-connect fittings
Includes canister wrench