Fully portable Battery operatec Automatic shut-off function Low battery indication function Made in the USA FEATURES: Fully portable Battery operated Automatic shut-off function Low battery indication function Two year warranty Made in the USA Utilizing the latest patented technology developed by RS MIZAR- these electronic gold testers accurately and quickly determine gold karat values of yellow- white- green and red gold shown on their LED display. These units also help identify platinum and can distinguish non-gold or gold plate from true karat gold. RS MIZAR Electronic Gold Testers use a liquid acid (included) and are very reliable- fast- safe- portable and are incredibly simple to use. The M24 Electronic Gold Tester is maintenance free and can automatically determine 9K- 10K- 12K- 14K- 16K- 18K- 20K- 22K and 24K gold in seconds THIS ITEM IS NON RETURNABLE.