The MaxSonar-EZ1 detects objects from 0-inches to 254-inches  (6.45-meters) and provides sonar range information from  6-inches out to 254-inches with 1-inch resolution.   Objects between 0-inches and 6-inches range as 6-inches.   The interface output formats included are pulse width  output, analog voltage output, and asynchronous serial  digital output. Size: 2.2cm x 2cm x 1.6cm  (0.88 x 0.8 x 0.63 inches)