Sparkfun Ultrasonic Range Finder - HRLV-MaxSonar-EZ4 (SEN-11309)

These easy-to-use ultrasonic rangefinders from Maxbotix work the same way as the EZ line that you know and love, but this new high-resolution series features 1 millimeter resolution! As with the rest of the Maxbotix range finders, these sensors feature Analog Voltage, RS232 Serial, and Pulse Width outputs making them easy to interface with any microcontroller. These sensors have a maximum range of 5000 mm (195 inches) with virtually no dead zone (although objects closer than 30 cm will typically range as 30 cm).