speed control heatsinks?
 

ok so every once in a while while looking at electric rc's i notice that the heatsink is not on the speed-control. i have wondered about this sense i was a little kid starting out in rc with the origanal rc-10 my dad gave me, and he used an rc-10t . man that was a long time ago lol.
but yeah is there any reason behing taking the heatsink off , or is it just that they fell off and they couldnt find it ever again, lol.

Most of the time they fall off and either got lost or got tired of putting them back on.if it was mine i'd glue them back in place if they fell off that frequent.they are there to keep the esc cool