2 x 18650 Battery Holder with DC2.1 Power Jack - DFRobot
Series 3.7V Flat Tip Battery Holder Case for 3 x 18650 Batteries & 3.7V 2X 18650 Battery Holder Connector Storage Case: Buy Online at Best Prices in Pakistan | Daraz.pk
18650 Battery Case Holder, 4 Pcs 2 Slots x 3.7V 7.4V | Ubuy India
Buy 18650 3.7V 2 Battery holder Parallel or Series connector plastic case
18650 Protected Button Top battery Panasonic-Orbtronic (FREE Battery Holder) 3400mAh
Ltvystore 18650 Battery Case Holder, 4 Pcs 2 Slots x India | Ubuy
BU-302: Series and Parallel Battery Configurations - Battery University