This is a Racer's Edge RCE1625 5-function Mini/Micro Connector Charger Adapter. It connectors to chargers that use a standard 4mm port.
Racer's Edge provides a convenient charging solution for mini and micro air or surface models. Includes five of the most popular connectors in this category: Mini-Molex (Tamiya), JR-type receiver, JST, Hubsan-type, and Micro BLH/EFL.
