Most firing pin stops are cheap, mass produced, stamped parts, but they're not Bullet Proof either. A Bullet Proof firing pin stop is fully machined from super tough bar stock steel with great care to radius all corners resulting in a part that is many times stronger than a standard firing pin stop. A quality firing pin stop should fit snuggly in place, therefore this part does require minor fitting to your particular pistol for a perfect fit.
What was advertised was what was supplied. Description made it clear that this part was what I was looking for and it fit perfect.