This propeller is extremely well made and shaped for high performance and thrust throughout the rev range. 

This is the OEM Prop for the BIGHORN Balsa plane

Specifications

Brand                           SUNNYSKY/EOLO
Size                              EOLO 12/6.5
MAX Working Speed   10400rpm
Working Speed            9700rpm
Dynamic Balance         4000rpm <15mg
Weight                         40g
Material                       Composite
Category                      Integrated
Storage Humidity        <85%
Storage Temp              -10deg/c ~ 50deg/c
Working Temp             -20deg/c ~ 60deg/c