Mech. An average product at best. The attachments stick into the hand nozzle of my cheap vacuum cleaner, but the suction power is annoying. Seriously, once you've got the smallest of the hoses attached, it barely draws any air in because there's a permanent hole in the base. probably to prevent the naturally aspirated engine from burning out, but still. It allows me to reach some small spots in my car but is not 100% efficient. It's cheap so I didn't spend much, but I don't expect much from it either.