Sealyhams should not be over 31cms (12ins) in height, measured at the withers, and should weigh around 9kgs (20 lbs). Coat colours include white, white with lemon, brown, and blue. A great deal of black is undesirable, as is ticking (speckled).Some Sealyhams look like miny goats but,without the horns.
Sealyham terriers have been described as couch potatoes, "displaying an even temper and a calm and relaxed attitude". The breed standard calls for them to be friendly but alert.
Sealyhams are loyal, loving, independent, spirited, and affectionate. They are brave little dogs. It has been descried as "the most beautiful union between cheerfulness and courage." Sealyhams are not as rowdy as some of the other terrier breeds. They are somewhat reserved with strangers, fairly independent, and generally good with other pets, although they can get very dog-aggressive. Sealyhams like to bark. They are a little difficult to train but they can hunt, track and are good watchdogs. Sealyhams are good at catching mice and rats. They are best with older children who are considerate of dogs. Sealyhams are "pack" dogs. They appreciate being a key part of a family and welcome companionship with other dogs.
The Sealyham Terrier is a fairly healthy breed. The life expectancy of the Sealyham Terrier is around 12-15 years. There are a number of health problems to look out for with this breed, and this includes spinal problems, PRA, deafness, heart problems, cataracts, and glaucoma. Puppies should come with BAER certificates, and the parents of the Sealyham Terrier puppy should have CERF certificates.
