equipment questions

[dvasques]

Since it doesn't seem like I'm ever becoming a football official in the US, I thought I should focus on doing it well down here. SO I saw a link to a website selling Refs equipment and I got a few questions...

Flags: what flag would be better to get? the one with a centered weight or the ball center one?

Beam Bag: there're 6 options of beam bags and since I've never seen one I thought I ask what are the differences and which one to get

I saw on another Thread some Play Clocks that I found interesting but I have a problem with them. Down here I must yell out loud once the clock reaches 20 secs to go. 10 secs to go, and I must count down from 5. Don't suppose there's any clock what would vibrate those times for me, right?