OMPHOBBY M4 Helicopter Socket cap screw M2x16mm OSHM4077 Sale! from 149 /per Qty. Add to Cart This is a replacement socket cap screw (Thread length 4mm) M2x10mm for the OMPHOBBY M4 Helicopters Contents socket cap screw M2x16mm-4 Qty available:1 SKU:OSHM4077