Stretcher bars come with a slot and peg system for assembly. This product is exclusively meant for use in stretching flat canvas – it does not have a lip or rabbet like traditional picture frame moulding. Important: For stretcher bars, the size you enter into the calculator will be the outside dimension of the assembled stretcher bars. For example, if you want to produce a 16″x20″ stretched canvas, enter 16″x20″. Make sure you account for the amount of canvas needed to wrap around your stretcher bars, and still be able to easily staple. For S103-M, 2 1/8″ of excess canvas beyond the image is recommended for easy stretching. For canvases 40 x 30 or larger, it is recommended to order corner / straight braces for your stretcher bars – please indicate in your order notes if you’d like braces added: Straight braces will add: $37.10 Corner braces will add: $65.63
