What does OPTO & COB meaning? April 28, 2022 21:23 The term to describe how ESC is built. OPTO means there is no built in BEC COB means that you can connect your motor wire 'directly' to the ESC. so there is no motor wire coming out of the ESC Related articles EZRun Max 4 HV and Motor Quick Look The main cause (Root) of Capacitor damage Installing External Caps: Xerun XR8 plus / Ezrun MAX8 ESC paired with 6S application The best ESC and motor to run in a 1/10 2wd buggy and a 1/10 4x4? buggy ? RMA - Initiate Return Comments 0 comments Please sign in to leave a comment.