Totally redesigned to provide outstanding breathing performance. The Sherwood Octo maintains dedication to rugged reliability combined with ease of maintenance. The Sherwood Octo has been the overwhelming favorite for rental applications for decades because of its simple reliability. Features include: larger diaphragm for optimal response to inhalation, larger exhaust valve for decreased exhalation resistance, resilient silicone rubber seat, precision - ground stainless steel cam and Delrin lever for smooth effortless breathing, high impact housing for rugged applications, Hi-Viz yellow face cover, simple to maintain.