This high quality 15 minute, metal, analog stopwatch comes in a high impact plastic protective case with no batteries required for operation. 

The dial is divided into 30 seconds with 1/10 second graduations and has a 0 to 15 minute registry with easy to read display numerals.  Start, stop, and reset operations are accomplished by a single button by successive depressions.  Rewinding is done by counterclockwise crown movement every eight hours.  The stop watch is housed in a plated metal case with a high impact clear acrylic dial cover for better shock resistance.  It provides excellent accuracy with the mechanical 15 jewel lever movement. 

You can perform timing experiments or use this stop watch to measure your pulse, lap time, etc.