Holder Wire, the black and red two-wire design is great for easy soldering and connecting. Can receive the voltage 3.7V, 7.4V, 11.1V, 14.8V DC supply. The battery holder is fixed by a stainless steel . It is very convenient to install and replace the battery, and it is not easy to damage other parts. case with for Ardu Ino board microcontrollers, LED projects, toys, also replaces broken battery holders for many electronic devices. holder bundle with wire is suitable for and maintenance of all kinds of DC equipment, with screw hole on the bottom and wire pre-installed, it is easy to . Specifications: case Perfect for in electronics and small hobby projects. Battery type: for 1/2/3/4 x 3.7 V (battery is not included). Note: Please do not this battery box, only it for 1/2/3/4 x 3.7V output. Please do not the positive and negative directly. When connected, the cable will get hot. Material:plastic colour:black Package Contents: 4 * holder case single slot 4 * holder housing 2 slots 2 * holder housing 3 slot 2 * holder housing 4 slots Only the above package content, other products are not included. Note: Light and different displays may the color of the item in the a little different from the real thing. The measurement allowed error is +/- 1-3cm.