Numeric keypad allows for fast programming. Counts up or down for 99 minutes in intervals of 1 second. Clear audible ring at 0.  Comes with a belt clip for carrying; a flip-open easel for standing on bench; and a magnetic backing for mounting on refrigerators, incubators, etc.  Operates on 1.5V silver oxide battery. Dimensions: 2-1/2" x 2-5/8" x 5/8". Traceable® Certificate is provided. It indicates traceability to standards provided by NIST (National Institute of Standards and Technology)