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. » Gearmotors » 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 JGB37-550 DC Gearmotor – High Power (526 RPM at 12 V) GSM / GPRS A6 Development Board XL4015 5A Adjustable Step Down DC-DC Module (4 – 38 V input) 2pcs 1-inch Caster 2pcs FC-14p 2.54 mm Cable (30 cm)