HOBBYWING VENTILADOR 2507-12V Specifications ? Input: 7-12cells NiMH or 3-4S LiPo. ? Size: 24.5mm(L) * 24.5mm(W) * 7mm(H).? Weight: 7.2g ? Suitable for: XERUN-120A-SD, XERUN-60A-SD, XERUN-120A-1S-SD EZRUN-25A-H, EZRUN-35A, EZRUN-60A How to Use: For the above ESC, please choose different cooling fans in different applications. For 4-6 cells NiMH or 2S Lipo: Needn't change the 5V cooling fan on the ESC; For 7-9 cells NiMH or 3S Lipo: Please choose a 12V cooling fan or supply the 5V fan from the receiver (+6V); For 10-12 cells NiMH or 4S Lipo: Please choose a 12V cooling fan, and cut the output of the built-in BEC, then supply the receiver with an UBEC (An additional external DC-DC regulator);