Here's an unbelievable deal on these.  This sale is for one case of 21-count NEW original equipment Mansfield 206–1112 large size 3-inch flush valve.  Each one is complete with flapper assembly, bottom seal and nut.  This flush valve assembly would be used with Mansfield tank model numbers 106, 188, 3106, 3108, 3147, 3185, 3195, and 3916.  Your toilet tank model number is located on the inside back of the tank.  Any questions at all, don’t hesitate to ask.  4194969675.  Free shipping to the Lower 48 States only.