Battery Connectors-Molex 51021 Series

Molex 51021-0200
The Molex 1.25mm 2P battery connector is possibly the most common type of battery connector used in RC products. It has, over time become the connector of choice for RC manufacturers of receiver boards as well as batteries. It was originally introduced by E-flight for use in their BNF Ultra Micros such as the Vapor and PT17. As shown in the image at the bottom of the page, this connector is used in the popular NanoTech brand of batteries and embedded in the battery case. The receptor is available as both surface mount and inline types which have leads attached. This connector is often confused with the MCPX (PH2.0) connector, however the distinguishing feature of this Molex connector is its blade shaped pins and locating lugs which slide into slots in the sides of the receptor. The standard connector type is shown on the left while the “in-line” version with a recess on the top is shown on the right.

Molex 51021-0300
The Molex 1.25mm 3P connector is commonly used on micro receiver and servos. This connector is utilised in products from DelTang, Hobby King Micro, FlyDream, Walkera and others. The wiring configuration shown in the images here is the same as used in many HobbyKing products and micro linear servos as well as sub 2 gram servos. However, some manufacturers use the traditional Black, Red, White wiring configuration. For receptors, in-line as well as surface mount are commonly available. The distinguishing feature of this connector is its blade shaped pins and locating lugs which slide into slots in the sides of the receptor.