Craftsman CMCS300B V20 reciprocating saw

Stroke length is how far the blade travels back and forth on each stroke. A longer stroke removes more material per pass and clears chips faster, which helps in demolition and thick wood. Shorter strokes can feel more controlled in tight spots and on thin metal.

Strokes per minute (SPM) is the top no-load blade speed. Higher SPM cuts wood faster, while lower speeds, set with the variable-speed trigger or dial, give more control and longer blade life in metal. Read it together with stroke length, since both affect cutting speed.

Brushless motors use electronic control instead of carbon brushes, which generally means less wear, less heat and more runtime per charge. Brushed motors are simpler and often cheaper, and are fine for lighter or occasional use, though their brushes can wear out over time.

This lists how many batteries come in the box, if any. Tool-only (bare) listings include no battery or charger, which suits buyers already on that battery platform. Two batteries let you charge one while working with the other.

Amp-hours (Ah) is the battery's charge capacity. At the same voltage, a higher Ah pack runs longer between charges but is usually larger and heavier. Smaller packs keep the tool lighter for overhead and light work; larger packs suit saws, grinders and other high-draw tools.

This states whether a charger is included and which type. Chargers vary in output, so the same battery can take noticeably different times to charge on different chargers. Tool-only listings usually include no charger.

Max speed is the top no-load speed, in RPM for rotating tools. No-load means the tool is running free, so speed drops once it is working. On drills, many makers list a figure per gear: high for small bits, low for control with large bits or long screws.

This is the maker's published warranty term. Terms for tools, batteries and chargers often differ, and some depend on registration or exclude certain uses. Read the maker's terms for what is covered, how claims are handled and whether proof of purchase is required.