Snake Gaiters - Snake Bite Protection - Khaki Tan (XLarge)

My calf including jeans measures 14 in. Suggested answers suggest i purchase the "large" size . why is large size not available in "khaki"?

Do you have a size chart? I've got thick calf muscles

I have a 15 year old son what size do i need to buy

Can i get overnite shipping on these