I know a lot about blisters, having just bought a pair of these.
Today’s invention is a form of protection for blisters. It consists of a collection of felt cylinders (blue), supplied as a column with each cylinder joined to the next using a small cord.
The cylinders have an adhesive underside allowing them to be applied around the blister (whatever its size) as shown.
This creates a support ring which minimises the pressure on the blister while it heals. The support in turn minimises the tendency for the blister to be squeezed so that even more outer skin is painfully separated from the inner layers.