Poron makes terrific insoles
I've been lining all of my boots and shoes with Poron for 20 years. Millimeter for millimeter, nothing cushions so well for so long for so little bulk as Poron. When my plantar fasciitis flares up, I can add a second layer and still have plenty of room.  I've been spending about $10 per insole pair, but now with this sheet, I can triple the bang for my buck.  As another reviewer pointed out, what you get is the light blue sheet that's shown on the bottom in the photo, not the one with the dark blue lining.  And that's what I wanted.  Over the years, I've come to prefer the bare bones, slick surface on both sides, pure Poron.
Rating: 5 stars