Dual 18650 charger

My son needed a charger for 18650 batteries for his bicycle light so I designed this. Printed in PLA, it uses a 1.3mm DC input socket, 2x 1-cell LiPo charger boards, battery connectors (2x springs and 2x end plates), a 5V DC wall wart, a length of ribbon to remove the batteries, some adhesive or double-sided tape and some hookup wire.

The charger boards I used are http://www.aliexpress.com/item/1Pcs-Dual-TP4057-Lithium-Battery-1-A-LED-Charging-Board-Reverse-Connect-Protect/32368102064.html an