A kitten's first flea treatment is usually the first time an owner has to trust a product completely — there's no obvious sign the fleas that would have turned up simply didn't, and a spot-on works or it doesn't without much visible evidence either way.

This one is a fast-acting spot-on containing imidacloprid, applied to the skin rather than given by mouth, and Johnson's say it kills fleas on contact with your cat and in the surrounding area, with up to two months of protection from the pack. It comes as two vials, each giving up to four weeks of cover, and it's for cats and kittens up to 4kg and over 8 weeks of age.

• 2 vials (2-treatment pack)
• Each vial gives up to 4 weeks of protection
• Kills fleas on contact, on the cat and the surrounding area
• Contains imidacloprid
• For cats and kittens up to 4kg, over 8 weeks of age

On the weight and age limits. These are the two figures actually printed on the pack — 4kg and 8 weeks — and Johnson's don't give a lower weight cut-off beyond the age, so a very small or unwell kitten is a question for your vet before you apply anything, spot-on or otherwise.

Who it's for: owners of a kitten or small cat starting flea protection for the first time, who want a full two-month cover from one small pack rather than buying single treatments as they run out.