This charger is designed to work with our replaceable lithium (LFP) batteries. It is safe, and provides an optimal charge without making the battery overheat. There are other chargers on the market and some may have a lower price, but they may have unpredictable effects since single-cell batteries have no safety circuits built in. We only recommend using this battery charger or the charger with the LCD screen (and provide no guarantee or support if our batteries are charged with other chargers). Pre-order now to ship with your Wind Instrument RB order.