I developed Plantar fasciitis in my left foot. The pain when putting weight on my heel, especially first thing, was excruciating. After researching various medical sites, decided to try insoles. And chose these. Good choice! They fitted in my slippers and trainers without any cutting (I take a size 8) and the effect was beneficial straight a way. Currently on the second day of use, and walking is easier and pain much reduced. I've ordered another two pairs.