http://www.validyne.com/product/dr800_draft_range_transmitter/
The Validyne Model DR800 Draft Range Transmitter is designed exclusively for very low pressure measurement needs. It has a “true” full-scale range as low as ±0.25” H2O, making it ideal for air flow control applications. It can be turned down to ±0.1” H2O; higher full-scale ranges to ±100” H2O are available. The DR800 offers 0.5% accuracy and an operating temperature range of -20°F to +185°F. The total combined temperature effects are less than 3%/100°F.