OMPHOBBY M4 Helicopter Washers (Swashplate Driver Arm) OSHM4094 Sale! from 584 /per Qty. Add to Cart This is a replacement swashplate driver arm washers for the OMPHOBBY M4 Helicopters Contents Washer Φ2xΦ3.2x0.5-8 Qty available:1 SKU:OSHM4094