3mm to 4mm Coupling Hub Please allow 4-6 days processing before ship out. For gearmotors or similar motors, we don’t ship using epacket and will use regular shipping if needed. Please note that regular shipping like singapore post might take 45-60 days to deliver, epacket 20 -35 days to deliver Thank you for understanding. » All Products » 3mm to 4mm Coupling Hub This copper coupler can be used for connection of 3mm to 4mm shafts of RC toys, boats and helicopters. SKU: OTH27407972788 Price: 0.99 $ Product in stock SSL Certificate Quantity Updating cart... This copper coupler can be used for connection of 3mm to 4mm shafts of RC toys, boats and helicopters. Specifications Length: 20 mm Material: Brass Related Products Miniature MP3 Player Module JGB37-520 DC Gearmotor (88 RPM at 6 V) JGA25-370RC DC Gearmotor with Extended Axis (6 RPM at 6 V) Remote E3D v5 3D Printer Head (0.3 mm nozzle, 3 mm filament) 5pcs USB to 3.5 mm DC Jack Converter Cable