The Makita BSS501Z is a 18V Cordless 5-3/8 inch Circular Trim Saw - Tool Only. The Makita BSS501Z has ergonomically designed handle with soft grip which provides better fit and even more control. The blade wrench on the Makita BSS501Z stows away in the saw for fast and convenient blade changing. LXT Lithium-Ion provides longer run time, 5x lower self-discharge (for use any time) and 16 firm holding contact terminals (for constant high power). The Makita BSS501Zs 25-minute rapid optimum charger communicates with the battery throughout the charging process using the built inch chip in the battery and built inch CPU chip in the charger. It actively controls current, voltage and temperature to optimize battery life.