DESC: Specially engineered thermal slots maximize heat flow yet maintain a low surface temperature. Convenient pre-mounted wheels ensure safety and stability. With patented smart-snap wheels design, they snap place perfectly with no assembly required. Three heat settings let you adjust output levels, optimizing energy-efficient operation. 7 oil-filled fin heating elements for larger heating capacity. Unit is permanently sealed with pur diathermic oil for stable and efficient heating. Safety features include thermal cut-off, rust-resistant durable metal construction, fully enclosed heating elements and gently rounded design.