The rubbers on my AT4040SM mics have pretty much all failed (loosened or broke) within 5-10 years of purchase, so I had to buy these. This is an excellent product. Made of what looks like good quality silicone or similar, it's very strong, non-slip and only has limited stretch so it has a good grip on the mic. However, you should not have to spend 7EUR+VAT every five years for each mic you have, only to keep them from falling on the ground. But I have not found a suitable alternative. In case you might, these are the dimensions for the bands when brand new: 1mm thick * 7,5mm wide * 40mm diameter. Good luck.