This digital 90-minute timer is truly an easy-to-use time management tool. Simply twist the outer ring to your desired time, push play, and the display will show your time! And if children need to take a break, just hit pause! Plus, the magnetic back makes it a snap to attach to metallic surfaces like file cabinets and whiteboards. Great for timing everything from tests to group activities to help kids stay on track. Timer measures 3 1/2" x 1"; requires 1 “AAA” battery (not included).