Oscillating multi-tool

Fein Multimaster without blade attached

An oscillating multi-tool or oscillating saw is a multitool and power tool that oscillates (rather than rotating or reciprocating), powered by battery or mains. The name "multi-tool" is a reference to the many functions that this tool can perform with the range of attachments available. "Master Tool" is also a trade name used in North America, short for the original tool by Fein called the Multi-Master. Attachments are available for sawing, sanding, rasping, grinding, scraping, cutting, and polishing.