. This is a mini scale Retractable Tailwheel for .15 - .45 size planes. It is made of durable nylon and may be operated by either a servo or pneumatically, features a spring center, and is steerable. Includes a pre-bent wire axle but does not include a tailwheel. Can be floor or bulkhead mounted. If operating pneumatically, customer must purchase: #ROBQ2369 Air tubing #ROBQ2365 Air cylinder #ROBQ0215 T-connectors (to hook up with the main gear retract air system). If operating mechanically, customer must purchase: Pushrod Retract servo (standard servo may be used, but will operate too quickly). With either set-up, a pushrod is also needed for steering (could use SULQ3007, cable pushrod, 36").