Simple explanations of confusing product specs like PSI, GPM, watts, amps, volts, amp-hours, CFM, torque, lumens, and cord gauge.
Those letters printed down an extension cord are not random. Here is what S, SJ, T, O, OO, and W mean, how to identify outdoor-use cords, and why gauge alone does not tell you where a cord belongs.
An 18V label and a 20V MAX label can be more similar than the numbers make them look. DeWalt explicitly rates its 20V MAX platform at 18V nominal. Here is what that means — and what voltage labels do not tell you about tool performance or compatibility.
Cordless tool batteries are covered in numbers: 12V, 18V, 20V MAX, 2.0Ah, 5.0Ah, 8.0Ah, and sometimes watt-hours. Those numbers look like a simple ranking system. They are not. Voltage, amp-hours, and watt-hours describe different things. A larger number may mean more stored energy, a different tool platform, more weight, or a pack designed to supply…
If you are comparing pressure washers, you will see two numbers over and over: PSI and GPM. The problem is that most shoppers notice the bigger number first, and that is usually PSI. That makes sense. PSI looks impressive. A pressure washer with 3,000 PSI sounds much stronger than one with 2,000 PSI. But when…