Lascar EL-USB-2 USB Datalogger Temperature and Humidity
Lascar EL-USB-CO USB Datalogger Carbon Monoxide
Lascar EL-USB-2+ Relative Humidity and Temperature Data Logger
Voltcraft PH-100ATC pH Meter
Uni-T UT33D Digital Multimeter (Palm Size)
Buy Voltage Measurement Kit from LogIT – including the voltage adaptor with standard 4mm sockets and a probe and cable set with a wide range of connectors and probes.