Univen rubber o-ring blender gasket seals compatible with Black and Decker blenders. Package of two blender gasket seals. Compatible with Black and Decker blender models BL1900, BL1900R, BL2900, BL3900SKT, BL4900, BL5000, BL9000, BLKT5950C. Compatible with Black and Decker part numbers BL5000-08, 13281207 and 1000000013. A common replacement part, this seal sits between the top of the blade and the bottom of the jar. Only one seal is needed per blender. Measures 2.6" (6.6cm) outside diameter x 2.1" (5.3cm) inside diameter. Quality part by Univen, a family owned American business.