We sell a lot of rubber stair treads,  and one of the biggest problems we have is when people order square nose rubber treads for a round nose step and vise a verse.   It is really important to get the correct nose on your rubber stair treads so they match your step.  If they do not match, they will not last as long, especially if they are heavily traveled.   On heavily traveled stairs the nose will flex over and over again, and over time the nose will crack.  The nose on your rubber stair tread has to be supported.  We have two kinds of curved or round nose rubber stair treads.  We have the bullnose, which is usually on a wood step, the round radius goes all the way around and returns under the step.  The other kind is usually poured concrete and is just a radius, this was used back in the 50’s and 60’s.  If you have poured concrete with a large radius, then you are going to want to use the 622 Series Rubber Stair Treads Round Nose.   If you have a bullnose round nose, I would recommend the  1000 Series Rubber Stair Tread Round Nose.   Below are two examples, one is a round nose and other is a square nose.

the above image is a round or curved nosed stair tread. Notice how the radius is continuous, this would be ideal for a bull nose step.

The above image is a square nose rubber stair tread. Notice how the nose is 90 degrees and square

We offer a larger selection on Rubber Stair Treads on our website