Ducting Outlets & Accessories. All items for sale are in stock… Check the feedback from our many satisfied new and repeat customers. Webasto Heating Air Blower Assy for Dual Top 12v Heater. Dual Top RHA 100. Dual Top RHA 101. Dual Top RHA 102. Dual Top Evo 6. Dual Top Evo 7. Dual Top Evo 8. Please note: 12 volt only.