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. » All Products » 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 JGA25-370RC DC Gearmotor with Extended Axis (133 RPM at 12 V) 2pcs Miniature Ball Bearing (4mm internal diameter) SJ4000 FullHD 1080p Camera Antenna (433 MHz, 4 dBi) JGB37-550 DC Gearmotor – High Power (58 RPM at 12 V)