The D550S offers the most power-to-weight of any cordless drill/driver in its class. Patent-pending IQV™ technology ensures maximum performance, durability, and battery life. The D550 is compatible with both Lithium Ion and Nickel Cadmium 19.2V IQV batteries. Industrial keyless ratcheting chuck with carbide steel jaws guarantees industrial grade performance. Fifteen-position clutch plus drill mode makes the D550 ideal for a wide range of drilling and fastening applications.