suwimut 2 pack hourglass sand timer, 30 minute and 5 minute set sand clock timers for office, home, desk decoration, time management tool with wooden base stand (black and white) suwimut suwimut 2 pack sand timers are a clear, visible sign to other people in your office that you are in the middle of a focus session. by flipping your sand clock, you give yourself 30 minutes of an uninterrupted workflow. just make sure your coworkers know what you are up to.