No more disposable batteries! This rechargeable battery box 8878 has built-in Lithium polymer batteries for low weight and maximum power. Use it in your LEGO® Power Functions models and never have to use disposable batteries again!
- NOTE: You must use the #45517 10VDC LEGO Transformer to charge this battery box
- Motor speed can be controlled via the battery box speed control dial!
- Output voltage is 7.4 V!