Material: Polyester size: back length 8": back length 8",chest 11"-13",neck circumference 8"-9.5" back length 10": back length 10",chest 15"-17", neck circumference 9.5"-11" back length 12": back length 12",chest 16"-18", neck circumference 11"-12" back length 14": back length 14", chest 18"-20", neck circumference 12"-14" back length 16": back length 16", chest 21"-23", neck circumference 14"-16" back length 20": back length 20", chest 24"-28", neck circumference 16"-18" back length 24": back length 24", chest 28"-33", neck circumference 18"-22" back length 30": back length 30", chest 34"-40", neck circumference 22"-25" Warm tip: Please measuring your dog's back length, chest, neck circumference berore purchase,and please carefully refer to our description of the details.