electric back scratcher

They provide kneading/shiatsu nodes, rolling or vibrating motors, built-in heat, multiple massage modes/programs, and adjustable intensity levels. Some listings also note auto-reverse rotation and a 15-minute auto shut-off.

Most items are mains-powered and explicitly note "Battery: No Battery Used." Several listings include AC/DC adapters and must be plugged in rather than relying on an internal battery.

They use several methods: weighted construction to help hold the unit in place, integrated or adjustable elastic straps, and non-slip bottoms or attachment straps for chairs and car seats.

Several listings mention a 15-minute auto shut-off timer and overheat protection. Some product notes also include usage warnings such as "Adult Use Only."

Shown warranty periods include a 1 Year Limited Warranty for multiple listings and a 30 Day Limited Warranty for one listing.