Sand timer After the whole process flow of sand for 15 minutes, have a time period ends, respectively, ... for 5 mins, 10 min,15min Sand timer consists of three materials, namely, from Finland's spruce, orange sand, unbreakable ... spruce, orange sand, unbreakable glass4.Function:TimerAfter the whole process flow of sand for 15 minutes, have a time period ends, respectively ...