BCP 8pcs Plastic Li-ion DIY Battery Case Holder for 4x3.7V 18650 Batteries Go to amazon.com Related posts Top recommendation for 18650 battery 8pcs FeaturePackage included 8pcsMaterial: ABSBody size (L x W x H): 3-1/16 x 3-1/8 x 13/16inchesFor 4x3.7v 18650 batteriesNoted: battery is not included