Product review (1 stars): For an aftermarket part i am disapointed.
An aftermarket part should not cost this much. I repaired and rebuilt factory 4" Stainless Steel ball valves. The bonnet seal was larger and same material but cost less than a dollar when purchased in pks of 12.
For one small teflon seal, you can spend much less on Danco 80794 Valve Packing  and get the same job done. Danco 80794 Valve Packing is available on Amazon for $2,78