This is Master Airscrew's Fiberglass-Filled 12x6 3-Blade Nylon Pusher Propeller.
Suitable for any application from training and sport flying to
Factory-balanced 3-blade prop has NACA airfoils and holds true pitch
Accurately balanced to create a greater thrust at lower RPM
Constructed of glass-filled nylon
12x6 glass-filled nylon 3-bladed pusher propeller
Diameter: 12" (30cm)
Pitch: 6" (15cm)
Hole Diameter: 0.24" (6.1mm)
The general rule for converting a 2 blade prop to a 3 blade is to
subtract 1" from Diameter OR subtract 1 from the Pitch.
PER MASTER AIRSCREW: All 3- and 4-blade props are balanced
dynamically at the factory prior to drilling. The mounting holes
are then drilled slightly off center, if required, to properly
balance the propeller. As such, the mounting hole may be slightly
off center. Master Airscrew assures us this is perfectly normal
and will not cause problems during use.