Casfuy 2 Speed Dog Nail Grinder

Superseded by Casfuy's own six-speed model, this old two-speed design has a weaker motor and less fine control, even though the brand still appears in current budget roundups.

Superseded by the six-speed model that Wirecutter actually tested and described as the better grinder, yet it is still what most marketplace listings push. It coasts on Casfuy's early bestseller reputation.

The superseded first-generation model: a small battery, fixed low torque, and the exact shortcomings the 6-Speed was built to fix. It survives on old bestseller reputation; buy the Casfuy 6-Speed instead.

The superseded model that still dominates search results and cross-shopping; the 6-speed replaced it with a stronger motor and more usable range for roughly the same money.

A superseded model: Wirecutter flags even the 6-speed as slower than the top pick, so the 2-speed inherits the same weakness with fewer speeds and an older motor. It coasts on the Casfuy name while being outclassed by its own sibling.