Product Details:

R110-DU series:
R110-DU 36T-44T is a fixed style ; R110-DU  42T-44T is hollowed out style.
Hollowed out shape: Lightweight design, multiple auxiliary bars to enhance the rigidity and give consideration to the rigidity and weight

R92-8100 series:
R92-810 44T-60T is a aero style.
AERO style: Reduce the interference of transverse airflow, achieve the wind breaking effect of riding, and have a large area on the back.Hollow out, enhanced rigidity and weight optimization.

for:Shimano R8100 R9200 110BCD Crank