I am not sure but this is what I use on my bb
http://www3.towerhobbies.com/cgi-bin...?&I=LXMVE0&P=7 and
http://www3.towerhobbies.com/cgi-bin...?&I=LXAFE9&P=7 works perfect
I think it is easier to use than pull start...pressing a botton and not having to hold the car to the ground so its a one handed operation