The Copter Graupner Propellers, are by far the BEST BALANCED FACTORY PROPELLER

They are the best propeller for use in Multicopter

Specification:

-Diameter / Pitch: 23/10 cm
-All-up weight, approx.: 8,0 g
-Diameter / Pitch (Inch): 9/4 "
-Rotating direction: R and L (CW -CCW) 
-Piece/Pack: 1 Pair
-Diameter / Hub bore: StufenBohrung 5/8 mm
-Material: Polyamid glasfaserverstärkt

Size 9x4 inches

Hole: 5mm / 8mm.