It is 20 inch, Bill. In fact, you can go to Walmart and buy one of these kids guitars for about $30. http://www.walmart.com/catalog/product.do?product_id=3056458 Slap on the Pearse #7300 string set http://www.juststrings.com/jps-7300.html for about $6 and raise the strings using a nut extender for about $6. If you want to make it sound even better, remove the plastic saddle, and replace it with another length of the stainless steel rod.
You will end up with a cheap, version of what I am playing in the video. I know this because I actually did it. It was the inspiration to actually make myself a nice one. Aloha, -Konabob