A handheld car vacuum is the accessory people use most and look after least. Three habits keep it working.

Empty it every time

A filled bin cuts suction long before the battery does. Empty the cup after each use and tap the filter clean outside the car.

Wash the filter, then dry it fully

Most filters are washable. Rinse in plain water, then dry completely — a damp filter refitted into the unit smells within a day and reduces airflow.

Charging

• Charge with the cable supplied. A higher-output charger does not make it charge better.
• Do not leave a lithium battery charging unattended in a parked car in summer. Cabin temperatures in Thane in May are well above what a battery pack is rated for.
• Store it at roughly half charge if it will sit unused for a month.

What it will and will not do

Handheld units clear dust, crumbs and pet hair from seats and mats. They are not a substitute for a workshop wet-and-dry vacuum on soaked carpet — where a product page states wet pickup, it means small spills.

Suction figures

Suction is quoted in pascals on the product page. It is measured at the nozzle with an empty bin and a clean filter, which is worth remembering when comparing two numbers.