Pets: all comparisons

Dog harness sizes are the least reliable numbers in this category. In the dog harness comparison, only two of eight listings publish chest measurements, and four show a Medium while four show a Large, each with its own range, so check the variant you actually select. Chest girth decides the fit; phrases like "all breed sizes" say little. Six of the eight list two or more leash attachment points and four name a front chest clip, but a front clip steers rather than ends pulling.

For water, look at tank size and power. The cat water fountain comparison runs from 74 oz (2.2 L) to about 118 oz (3.5 L), and only two of the eight run on a rechargeable battery, one of them shipping without a charger. Only two makers give a noise figure, and both are their own numbers with unknown measuring conditions. Only two list dishwasher-safe parts, so plan on hand washing the rest, and five list a two-year warranty against none for two.

Seven of the eight automatic pet feeders run on a timer; the eighth is a gravity set with no timer at all. Only two list Wi-Fi. These listings describe dry kibble only, so wet food is out, and four name a 2 to 15 mm kibble range, which matters because large pieces can jam a rotor. Fit batteries as a backup, since a power cut can leave a pet unfed. The two multi-cat models do not mention recognizing individual animals, so a hungry cat can still eat from a neighbor's bowl.