<qa>  What is the femoral stem made from?The HIT Hip Replacement System HHRS is a Metal-on-Polyethylene MoP conventional hip prosthesis. The HHRS consists of a femoral stem, an acetabular cup and a Cobalt Chromium Molybdenum CoCrMo ball that articulates within a polyethylene liner. The ball sits on the acetabular cup, and the polyethylene liner is attached to the femoral cup, which attaches to the femoral stem, instead of the acetabular cup. The acetabular component of the HHRS consists of a hemispherical acetabular shell with a clustered screw-hole design. The outside of the shells are coated with titanium plasma to facilitate bone in-growth and provide secure intermediate fixation with the prepared bone surface at the site of implantation. The acetabular cup has a 3-hole design that accommodates three titanium alloy bone screws. Inside the acetabular cup is a male taper for assembly with the acetabular ball. The femoral component consists of a femoral stem manufactured from titanium and a mating cobalt chrome femoral cup lined with a highly cross-linked ultra-high-molecular-weight polyethylene UHMWPE. As with the acetabular cup, the femoral stem is porous coated using a plasma spray of pure titanium, which is intended to facilitate bone in-growth and provide secure intermediate fixation with the prepared bone surface at the site of implantation. The femoral stem incorporates a female taper for assembly with the male taper of the femoral cup. 