This size sasher is commonly used for quilt binding or for 1.25" purse straps if used in conjunction with a 2 1/2" Sasher.
Please note – the size on the Sasher is the finished folded width of the strip. You need to cut your fabric twice the finished size required. For the 1 1/4" Sasher, you would cut your strips 2 1/2".
If you are making straps, use two Sashers. example: For a 1" strap, cut your fabric four inches and use a 2" Sasher for the first fold. For the second fold, use a 1" Sasher.