timer
shower timer
water proof shower timer

digital timer

 

Options:
1) 1m59s for 2m timer
2) 2m59s for 3m timer
3) 3m59s for 4m timer
4) 4m59s for 5m timer
5) 9m59s for 10m timer
6) 14m59s for 15m timer
7) 19m59s for 20m timer
8) 29m59s for 30m timer
9) 59m59s for 60m timer

10) 99m59s for 100m timer