An evaluation kit from Sensirion designed for an easy and cost-effective assessment of the SDP31 differential pressure sensor. The kit consists of a USB stick with an adapter cable, and a SDP31 PCB-mounted sensor. The Sensirion EK-P4 viewer software, the SDP31 datasheet and a quick start guide can be downloaded from the Sensirion website. The viewer software needs to be installed on a suitable PC and allows measurements at variable resolution, displaying differential pressure in Pa and inches water-gauge. Absolute or relative timing may be chosen and data are graphically displayed. The software has the capability for easy data-logging and data may be exported.