“Easy to apply to any shoe and we’ve even put one each on our children’s runners. Feet that are warm to sweaty seem to be best as there is better contact with the strap and transmission of electrons through electrolytes to ground. Next time I buy new runners I’ll have a new Erthe strap ready to install out of the box. It’s just not feasible to get to the beach every day or into a grassy park so I hope these straps will work on the days we need extra help earthing ourselves.”