Expansion Joint Foam is manufactured from high quality, closed cell, chemically cross linked polyethylene foam.

It is light weight, highly durable, moisture resistant material ideal for concrete construction where expansion joints and element separation is required. Has a 10 mm tear off strip along one edge to pour sealant into the gap created.
Expansion Joint Foam is available in 10 mm thick in either plain or adhesive backed. Width varies from 50 mm to 300 mm wide and all rolls are 25 Meters in length.

Expansion Joint Foam is also known by other names such as Abelflex. Abelflex is a brand name for expansion joint foam but any brand of expansion joint foam can be used where Abelflex has been specified on a project. https://www.cornellengineers.com.au/all-about-abelflex/