Abstract: A frame that is configured to hold a window air conditioner unit includes a main frame body having an opening formed therein for receiving the air conditioner unit. The frame includes a pair of adjustable side support frames that are slidingly coupled to the main frame body for filling a space between sides of the air conditioner unit and sides of the window frame. Each of the side support frames includes a take-up device for securing the frame within a window channel of the window frame. The take-up device has a fixed stop fixedly attached to the side support frame and an adjustable stop that is movable in a forward-rearward direction. The take-up device further includes an actuator that is accessible to a user along the main frame body and is configured to move the adjustable stop in the forward-rearward direction.