You may order additional diameter on any large regular leather, plain finish or vegetable-tanned collar, including flannel lined, for an extra charge of $5.00 per inch of diameter, up to three additional inches, for use especially with larger birds and foot injuries. In order to order an additional-diameter collar, you must first order the collar, indicating product number for the collar and then order the additional diameter you wish to order on the collar you have indicated as an additional item, using its own product number. Note: 1" of diameter equates to approximately 1/2-inch of length from nape to hemline.