An electronic tape measure...that's basically what this is. This Distance Measuring Kit sends out beams of sound waves that 'bounce' back and are calculated. The site says it all with the following information,
"Our Electronic Distance
Measuring Tool has a built-in calculator to add linear measurements and
compute areas and volumes. Intelligent software improves accuracy and
the easy-to-understand instructions complete the attractive package.
This
electronic measuring tape is reliable, accurate, precise, and easy to
use. With 7 memories ( 5 memories for registering results, 2 memories
for calculation of cubic volume and square area), no calculator is
required to figure out area or volume."
With a maximum of 59 feet and a minimum of 1 ft. 11 in., this could be put to practical use in the home and on the job. It's priced at just around $100 and the site offers a discount if you buy more than one. Visit the link to see more details on the JT60 Intelligent Ultrasonic/Infrared Professional Distance Measuring Kit...that's a mouthful!