Battery runtime is capacity divided by draw. Capacity is measured in watt-hours: volts times amp-hours. A 20V 8.0Ah pack holds 160 Wh; the Qrachic 20-inch blower carries two, so 320 Wh on board. Its motor is rated 1,300 W, so at full load the packs last about 15 minutes. The 12-inch shovel carries two 20V 6.0Ah packs — 240 Wh total — against a 1,000 W motor, which works out to roughly 14 minutes at full load.
Those are worst-case figures: full load is dense, wet snow at a fast walking pace. Snow that is lighter, a slower pace, or a narrower pass all lower the draw and stretch the same charge. That is why we do not publish a single runtime number — the range depends on the conditions, and a number measured in a lab would not match your driveway.
