Extend your capacity – the TimberLine attaches to factory racks with raised side rails to expand your carrying capacity and deliver maximum rooftop versatility. Secure and super-sleek, they are quiet, simple to install and work with all of Yakima's bars. Complete set of 4 TimberLine Towers. The totally new Yakima tower for vehicles with raised side rails. Advanced tower architecture is sleek, strong and quiet. Strong, durable stainless steel strap to accommodates a range of rails.