1 sprue with 4 bases.
Enough pieces are included to convert 4 bases.
These adapter rings are designed to wrap around existing bases to increase them from 25mm to 32mm.
We have found these work fairly well on 25mm bases from:
GW, Forge Craft Games, Micro Art Studio, & Hitech.
Product made by Retaris Inc. and more information is available at https://www.eccentricminiatures.com/