Instruction: Parse the product information to locate the target attribute, and then provide the extracted value of the target attribute and its source in the output, specifying None if the attribute is not present.

Input:
Product title: Sunex SX4345 1/2-Inch Composite Impact Wrench
Product description: The tools you need to get it done-whether drilling, driving, grinding, cutting, sanding, spraying or hammering, Sunex Tools Air tools supply you with power, flexibility and exceptional value. When you need performance, you need Sunex Tools Air tools.
Product feature: 750-Feet Pound of quiet power, 1100-Feet Pound of breakaway torque, One hand forward/reverse, Quiet Tech exhaust system delivers 82 dBA, Specificat ions: square dr. 1/2-Inch, torque 750-Feet Pound, working torque 50-540-Feet Pound
Product brand: Sunex Tools
Target attributes: Voltage
Answer: attribute: voltage
value: None
source: None