A fluid end made of a plurality of fluid end sections positioned in a side-by-side relationship. Each fluid end section is made of a housing having a discharge bore and an intake bore formed therein. A fluid routing plug is installed within each housing and is configured to route fluid throughout the housing and between the discharge and intake bores. The fluid routing plug carries seals that engage sealing surfaces formed within the housing. A number of features, including the location of seals within bore walls and carbide inserts within valve guides, aid in reducing or transferring wear within each housing.