I'm looking to get a personal timer that has selectable round times and rest times to make it easier to workout at home on my heavy bag. The professional gym ones I'm finding all cost over $100. I just want something simple and inexpensive (under $30?). I saw one from Everlast for around $12.99 but read horrible reviews on Amazon.com. It seems like something easy to make, but I can't find anything.

Does anyone have any suggestions? Thanks for the help.