ohh and forgot to say
that Hobbywing Pentium 40A Brushless ESC With BEC 3A x1
how do i know if it comes with seperate BEC?

and what is the importance of having the switch one?

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update*


im just going to buy the 2 completely seperate now so i know im getting them seperate

first one im getting is:
RC Mystery 40A ESC Brushless Motor Speed Controller Heli NO BEC

and i have 2 becs to choose from:
TURNIGY 3A SBEC BEC w/ Noise Reduction Switchmode

and
RC UBEC BEC device Switch Mode 5v 6v 3A Max 5A NEW

are they noisy or not cuz i can buy turnigy bec with noise reduction for a few extra dollars

Ubec wieghs 6grams less than other bec

let me know what you think and are they compatable with the belt cp v2 (i think they are)