Silent a Watch (Good for Sat)+reversible

This year i took the sat test.. and i was horrified when i read that "any watch that even beeped will get your score canceled" ..ok not the exact words but thats what it mean
so i had my trusty Casio F-200 watch with me which beeped everytime i pushed a button..
i searched online and "special exam silent watch" "made specially for official test" cost a painful 40 USD... my watch cost me 25RMY= 8USD

so i open up my watch and see what i can do
items needed
1) Casio F-200 watch (i dont know about other watches)
2) small "cross" bit screwdriver
3) duct tape
4) 2-10 minutes

*disclaimer*
I am not responsible for any damage done to you or your property, this is information provided showing my experience with my watch, process my differ with different make, model or even individual watch
attempt at your own risk

first step is to unscrew the four small screws at the back, make sure you keep them well

ok look at your watch and find the small spring
(see picture for an idea)

now, look at your back plate
that is the buzzer (see picture)
and the small exposed part there is where the spring contacts it to make it beep

just use some duct tape or any insulator to block it i suggest duct tape or paper

close it up and screw it then your done ^^

(the black piece is te rubber that makes it water proof)