StainoInterdental Brush Refills, Large Cylindrical, 72 Brushes/36 Units Per Box

Expensive but work fine.

Size is perfect! Made with durable materials! Does exactly what a proxy brush is suppose to do, clean areas between your teeth! Excellent!

These are great. I use them instead of the Oral-B cylindrical brushes. They work the same, but these last a lot longer before the metal core fatigues and the brush breaks off.