Boston fit improvement. I have quite narrow feet and these inserts, though not ideal (minor sticky separation sound when you lift off while walking) have made them functional to use. They otherwise
New w/o Tag Birkenstock Professional Replacement Footbed Black Reg Select Size | eBay
Profi Birki Replacement Footbed Black | BIRKENSTOCK
Profi Birki Replacement Footbed Black | BIRKENSTOCK
Profi Birki Replacement Footbed Black | BIRKENSTOCK
Birkenstock Birko Balance Arch Support Natural | Insoles – Footwear etc.