I have the ST1511T. On Egos website it takes me to parts for ST1510T and recommends this bumper cap 2825469004 as a replacement. Just visually the parts look different as the bumper piece(at the very bottom) on my model was much smaller than what is on this model. In addition, after receiving and installing the this new bumper it does not operate the same. The bumper feed functionality does not work smoothly anymore. Before I was able to tap on the ground to feed more line out now I can not. It was struggle to get this function to work and very frustrating.
I would have given this a 5/5 star as the product ship quick and was a good price but wanted to warn others of what I found.