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What is a back strap? I often hear the question when I advise people by using FlexHorse boots.

Back strap is a strap that goes over the the bulbs and attaches to both sides of the boots with metal rivets. The image below shows a red back strap on the boots.

Back strap should be fastened firmly. You will be able to put your one finger just above the top edge of the boot and between the strap and the leg. Then the strap is tightly closed. Back strap will flex in motion, so its flexible feature allows space for expansion on the bulbs when the foot hits the ground.

In our instructions, it is advisable to adjust the back strap to the correct length for the horse's leg. 
If there is more than one hole extra left under the rivets, it is advisable to cut off the extra holes. This will ensure the strap not to open.

The photos below shows how to adjust the back strap for optimal adjustment of the horse. The strap should follow in the same line as the "alley" in the shell. This is not always the case, almost yes.
Back strap should not be at the top of the hollow of the heel, but in the middle of it on the top of the bulbs.

We hope these instructions will help you to get most out of the Flex Hoof Boots!