Super substitute, but you should bring some skill

The ear cushions fit my Sennheiser HD515. The substance is more black than anthracite as in the original. The pad a little harder, still allows the headphones for hours wear. Beautifully warm ears ;-)

The quality is great, except for a small blemish on the back, which is not visible but later. Unfortunately, no guidance is, therefore, I'd write a:

The old pad you have to pull or pry off with a screwdriver. Then you have the plastic ring which is actually festgeclipst, pull out from the old pad below.
The hairy part is the back reinzubekommen the new upholstery. After that everything just squeezes again. But it may be that the plastic edge at the back is a little too wide, then you have to help out with a pair of scissors.