ᐅ Solid Insulation Foam Rod – Description and Source

Hello everyone,

I have a question for you.
Can anyone tell me what this material is called and where I could buy small quantities of it in the Essen (NRW) area?

It is a solid, dark gray foam material without any slits or holes, similar to Armaflex.
I need it in diameters of about 2 cm (0.8 inches) and about 1 cm (0.4 inches).
Unfortunately, I no longer remember the name, and I couldn’t find it at the hardware store I visited today. However, I think it originally comes from a hardware store.

Thanks in advance!

Best regards,
Max

Hello,
this is a tile grout filler material.
Now, only a source for material sold by the meter in Essen would be of interest.