<https://www.fujiracing.com/product/stainless-steel-exhaust-valve-set-fren122-fren123/>
<http://schema.org/description>
"Swirl polished heads for smoother air flow over the valve. Back cut to reduce valve weight for higher RPM, higher boost pressure,"
<https://www.fujiracing.com/product/stainless-steel-exhaust-valve-set-fren122-fren123/>