It's about as heavy as a Horse.
It's about nine-tenths as heavy as a Grand Piano.
In other words, 420 kilograms is 0.930 times the weight of a Grand Piano, and the weight of a Grand Piano is 1.10 times that amount.(for Steinway & Sons, Model D Concert Grand Piano)
A Grand Piano, of the kind used for concert performances in large music halls, weighs 450 kg. Well-made pianos such as this may last 75 to 100 years.
It's about four-fifths as heavy as a Polar Bear.
In other words, 420 kilograms is 0.8140 times the weight of a Polar Bear, and the weight of a Polar Bear is 1.230 times that amount.(Ursus maritimus) (adult, male)
An adult, male polar bear weighs between 352 and 680 kg. Polar bears are so heavily insulated by their 9.9 cm (3.9 in) layer of blubber that they are often difficult to detect using infrared photography sensors.
It's about four-fifths as heavy as a Grizzly Bear.
In other words, 420 kilograms is 0.8060 times the weight of a Grizzly Bear, and the weight of a Grizzly Bear is 1.240 times that amount.(a.k.a. brown bear, a.k.a. silver bear, Ursus arctos horribilis) (Adult, male, coastal area population average)
An adult, male grizzly bear from a coastal area (where food is plentiful) can weigh up to 521 kg. In spite of their tremendous size, grizzly bears can run at speeds of up to 55 kph (34 mph).
It's about three-fifths as heavy as a Cow.
In other words, 420 kilograms is 0.620 times the weight of a Cow, and the weight of a Cow is 1.60 times that amount.(for Holstein, a.k.a. Holstein Friesian, a.k.a. Friesian, Bos primigenius) (adult, heifer)
A mature Holstein cow (the well-known black-and-white, spotted breed of cow) typically weighs 680 kg. President William Howard Taft (1909 - 1913) kept a Holstein cow named Pauline Wayne on the White House grounds — a gift from a Wisconsin senator and the source of the First Family's milk.
It's about one-and-seven-tenths times as heavy as a Pig.
In other words, the weight of a Pig is 0.590 times 420 kilograms.(Domestic pig, Sus scrofa domesticus, a.k.a. S. domesticus) (adult)
Domestic pigs weigh between 50 kg and 450 kg. The titular character "Babe the pig" in the 1995 family film was played by 48 different American Yorkshire piglets due to the length of filming and the rate at which piglets reach adulthood.
It's about one-and-four-fifths times as heavy as a cubic meter of Snow.
In other words, the weight of a cubic meter of Snow is 0.560 times 420 kilograms.(Freshly fallen, standard conditions; measurements taken in Norway, 1965-68)
One cubic meter of freshly fallen snow under standard conditions weighs an average of 230 kg. Assembled in 2008, the world record largest snowman was constructed of 5,900,000 kg of snow and stood 37.21 m (122.1 ft) tall.