Belimo LHQX24-1-100 : Non-Spring Return Linear Damper Actuator, 24VAC/DC, 22 lbf, 4in Stroke, On/Off, Floating Point Control Input, 3.5 Second Run Time, 5-Year Warranty (MUST BE CONFIGURED BEFORE PURCHASE; please contact us at 888-739-8400. Price subject to change based on options selected) (Customized products are non-returnable and non-refundable)