Different than other boots, because of the patented lacing system. The boot will open large enough to accommodate the wide base of a hoof. Application is fast and does not require great strength. The boot is tightened with an easy turn of a dial, offering precise fit. Closure is solid. Pressure points are eliminated. NO need for separate left or right boots. A convenient boot to have and use. Boa Boots are sold in pairs. Size Width Length #00: 3 1/2"- 3 7/8" 4 - 4 3/8" #0: 3 7/8"- 4 1/4" 4 3/8"- 4 5/8" #1: 4 1/4"- 4 7/8" 4 5/8"- 5 1/8" #2: 4 7/8"- 5 1/4" 5 1/8"- 5 3/8" #3: 5 1/4"- 5 7/8" 5 3/8"- 5 7/8" #4: 5 7/8"- 6 1/4" 5 7/8"- 6 1/4" #5: 6 1/4"- 6 11/16" 6 1/4"- 6 11/16" #6: 6 11/16"- 6 15/16" 6 11/16"- 6 15/16" #7: 6 15/16"- 7 3/8" 6 15/16"- 7 3/8"