A catalyst system comprising the product of the combination of: a) a first metallocene catalyst and a second metallocene catalyst independently selected and represented by the formula wherein: M is hafnium or zirconium; each X 1 and X 2 is, independently, a hydrocarbyl radical having from 1 to 20 carbon atoms, hydride, amide, alkoxide, sulfide, phosphide, halide, diene, amine, phosphine, ether, or X 1 and X 2 is part of a fused ring structure; each of R 1 , R 2 , R 3 , R 4 , R 6 , R 7 , R 8 , and R 9 is, independently, a hydrogen, halide, alkoxide or a C 1 to C 40 substituted or unsubstituted hydrocarbyl group, or a pair of R 1 , R 2 , R 3 , R 4 , R 6 , R 7 , R 8 , and R 9 form a substituted or unsubstituted fused ring structure; T is a bridging group comprising, independently, one or more Group 14-16 atoms; and each R a and R b is optional and independently, a hydrocarbyl or a substituted hydrocarbyl; b) at least one activator; and c) optionally, at least one support; characterized in that the bridging group T of the first metallocene catalyst is a silicon or germanium atom; the bridging group T of the second metallocene catalyst is a Si-O-Si or a Si-N-Si group; the metal M of the first metallocene catalyst is hafnium; and the metal M of the second metallocene catalyst is zirconium. a) a first metallocene catalyst and a second metallocene catalyst independently selected and represented by the formula wherein: M is hafnium or zirconium; each X 1 and X 2 is, independently, a hydrocarbyl radical having from 1 to 20 carbon atoms, hydride, amide, alkoxide, sulfide, phosphide, halide, diene, amine, phosphine, ether, or X 1 and X 2 is part of a fused ring structure; each of R 1 , R 2 , R 3 , R 4 , R 6 , R 7 , R 8 , and R 9 is, independently, a hydrogen, halide, alkoxide or a C 1 to C 40 substituted or unsubstituted hydrocarbyl group, or a pair of R 1 , R 2 , R 3 , R 4 , R 6 , R 7 , R 8 , and R 9 form a substituted or unsubstituted fused ring structure; T is a bridging group comprising, independently, one or more Group 14-16 atoms; and each R a and R b is optional and independently, a hydrocarbyl or a substituted hydrocarbyl; M is hafnium or zirconium; each X 1 and X 2 is, independently, a hydrocarbyl radical having from 1 to 20 carbon atoms, hydride, amide, alkoxide, sulfide, phosphide, halide, diene, amine, phosphine, ether, or X 1 and X 2 is part of a fused ring structure; each of R 1 , R 2 , R 3 , R 4 , R 6 , R 7 , R 8 , and R 9 is, independently, a hydrogen, halide, alkoxide or a C 1 to C 40 substituted or unsubstituted hydrocarbyl group, or a pair of R 1 , R 2 , R 3 , R 4 , R 6 , R 7 , R 8 , and R 9 form a substituted or unsubstituted fused ring structure; T is a bridging group comprising, independently, one or more Group 14-16 atoms; and each R a and R b is optional and independently, a hydrocarbyl or a substituted hydrocarbyl; b) at least one activator; and c) optionally, at least one support; characterized in that the bridging group T of the first metallocene catalyst is a silicon or germanium atom; the bridging group T of the second metallocene catalyst is a Si-O-Si or a Si-N-Si group; the metal M of the first metallocene catalyst is hafnium; and the metal M of the second metallocene catalyst is zirconium. characterized in that the bridging group T of the first metallocene catalyst is a silicon or germanium atom; the bridging group T of the second metallocene catalyst is a Si-O-Si or a Si-N-Si group; the metal M of the first metallocene catalyst is hafnium; and the metal M of the second metallocene catalyst is zirconium. <EOS>