Machined in 4140 steel and black oxide coated, OPF-M17, ACRO is a new member of our OPF (Optics Platform, Forward Controls) line. We again eschew aluminum for this application, and continue to use steel as other OPF plates, we prefer steel plates for steel screws. 4140 steel costs more and takes longer to machine, we use it extensively on other products. We do not deem light weight to be of particular use in this application, but consider reliability and durability far more useful and important qualities.
