Cordless oscillating tools move their blade or attachment from side to side in a small arc at high speed for precise cutting, scraping, sanding, and polishing. The greater the arc (oscillation angle), the more aggressive the action. Also known as oscillating multi-tools (OMT), they accept various blades for specific tasks and materials. The blades can be set at different points around the tool head to accommodate workpieces. Oscillating tools make plunge and flush cuts for jobs such as cutting installed trim, undercutting door jambs, and cutting openings in floors and walls for outlets and ducts. They can also scrape off excess material, remove grout and caulk, and perform detailed grinding and sanding. These tools run on batteries, so they are more portable than corded tools and allow use where access to a wired power source is unavailable. They use brand-specific batteries, which fit different tools from the same manufacturer. Battery voltage and series must be compatible with the tool.