This is a perfectly sized pocket to slide in diaper inserts, like charcoal bamboo inserts. (earlymomentsmatter.org)
Vlokup charcoal bamboo inserts fit most One Size cloth diapers, sized at 13x5 inches each. (amazon.ca)
The Naturally Natures Soft Baby 5 Layer Charcoal Bamboo Inserts Reusable Liners for Cloth Diapers with Gussets (Pack of 12)(Grey) is made of bamboo Viscose and micro-fleece. (babieslounge.com)