. HSP R025 One Way Bearing & R020 Pull Starter for 16-21 Nitro Engine 1/10 RC Car , Buggy, Truck, Truggy . Specifications: Item Number: R020+R025 Material: Plastic + metal Parts Name: Pull Starter + Hex Nut One Way Bearing (12MM) Fits for vertex VX 16 18 21 nitro engines , Please be notice this pull starter is not suit for all 16-21 Nitro Engines, please make sure the size suit for you before order it. For vehicle type: 1:10 nitro engine car 12mm Hex Size: 32mm * 32mm Hole to Hole: 27mm Package Including: 1 x 1:10 Pull Starter 1 x Hex Nut One Way Bearing (12MM)