The product has been designed to provide higher stabilization than the sponge and the Nelson collars following a neck trauma or cervical disc hernia. Made of plastizote and suitable for MR monitoring as it does not contain any metal parts. Philadelphia Neck Collar Philadelphia Neck Collar Size The Armo Line Philadelphia Collar is available in three different sizes, enabling you to choose the size that fits you perfectly. Please measure around your neck and select the appropriate size from the table: Size in Cm in Inches Small 34 - 36 cm ~13¼? - 14¼? Medium 36 - 38 cm ~14¼? - 15? Large 38 - 40 cm ~15? - 15¾? Easy Return All products purchased on the Website may be returned or changed with an other size of the same product for once, if you inform us of your intention to change or return the product(s) within 7 days after the purchase. The notification should contain whether you want to change or return the product and (if you want to change the product), the new size and colour details.