Single timer. Includes belt clip, magnet, and foldaway stand on the back of the timer! The MyChron individual student timer is a great tool to enrich many of your classroom activities in: science, reading, mathematics, assessment, student time management, physical education, etc.Features: Easy to use 3-key operation: LAP - START/STOP - ON/RESET Easy to read display in: hours, minutes, seconds, hundredths/seconds With use of lap key elapsed time can be read while timer keeps running Automatic shut-off when not in use Handy size for any age student to use Includes lanyard for MyChron to be worn around neck See-through storage box for easy, visible classroom management Power source: one lithium button battery (G10-A or similar) External dimensions: 5cm (2") x 5cm (2") x 1cm (7/16")