2mm 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. » Other » 2mm to 4mm Coupling Hub This copper coupler can be used for connection of 2mm 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 2mm to 4mm shafts of RC toys, boats and helicopters. Specifications Length: 20 mm Material: Brass Related Products Power Supply Module (220 V to 5 V, 2 A) DS3231 I2C Precision Clock with AT24C32 Memory JGA25-370 DC Gearmotor (26 RPM at 6 V) Remote E3D v5 3D Printer Head (0.2 mm nozzle, 3 mm filament) Wheel and Mounting Kit for 25 mm Gearmotors