A low cost, effective and quality solution for your company's signaling needs. Made and tested in the U.S.A. Guaranteed to be heard up to a mile; loud enough to be heard over machinery and other noise. Typical uses include: primary alarm system in a small firm, back-up system for a large company, warning alert in a confined space, injured worker alarm or an alarm against an intruder, thief or unfriendly animal. Audio Range: 1 mi; Diameter: 4 1/2"; Length: 9".