This is a set of 11 Saran Wrap cores. They are the red cores from Asahi Kasei's 50-meter Saran Wrap. All are the same size. Length: Approximately 23 cm Diameter: Inner diameter 2.2 cm, outer diameter approximately 2.7 cm at the widest point. I collected these for a year for my daughters' crafts and art projects, but I have a lot left over, so I'm selling them. I have two sets of the same item, and I am listing both. Great for elementary schools, kindergartens, daycares, childcare workers, and kindergarten teachers. Ideal as a craft material. Perfect material for handicrafts and DIY projects. Can be used for children's crafts and art projects. Please consider purchasing.