An insert is a piece of plastic or plexiglas that is cut to fit your specific brand and model of sewing machine. The Insert is used when the sewing machine is in the Flat-Bed Mode, this is when the needle plate of the sewing machine is level with the top of the cabinet. The Insert fills the gap between the sewing machine and the opening of the cabinet to create a flat working surface.
Horn cabinets require an insert designed specifically for your machine make and model. Don't forget to specify your cabinet and sewing machine make and model in the shopping cart.
If you are unsure of the manufacturer or model number of your cabinet, please measure the dimensions of the hole that the insert will go into, and write it in the text box in the cart.