“I have a pair of 15 year old ems boots that look to be a cross between the tahoe and summit, definitely alico style. They are so old I am unable to determine what size they are, and I am hoping to order a new pair of summits :) The vibram sole measures a bit over 11.5 inches. I expect these boots were 9 or 9.5. Can you assist as I would like to order the same size.”
A 9 has an insole length of 11", so you will want an 9.5 or 10 for more comfort. If you wear thick socks you will want a 10.