ITEM NAME:5pcs 3.17mm Aluminum Bullet Propeller Adapter Holder for Brushless Motor Prop Description: 100% Brand new and high quality Delicate workmanship, durable in use Suitable for brushless motors and speed controllers Material: Aluminum Color: Silver Specification: Motor Axle hole diameter: A: 3.17mm (5mm output shaft) B: 3mm (5mm output shaft) C: 3mm (6mm output shaft) D: 4mm (6mm output shaft) E: 3.17mm (6mm output shaft) Size Chart: As described above, please make sure the information of size before making a order. Package Includes: 5x Aluminum Propeller Adapter SKU: FUZ0001697276006032.5x Aluminum Propeller Adapter. Material: Aluminum. SKU: FUZ0001697276006032. Size Chart E: 3.17mm (6mm output shaft).