The Nathan AirChime K3LA has long been the leader in commercial railway horns. This horn is the most commonly used horn on diesel locomotives across the US and is the same horn everyone's familiar with when a diesel locomotive comes barreling down the tracks.
This K3LA is an American tuned version of the K3 with a low-profile mount to make it easier to install on trucks (not intentionally). The K3LA is an amazing horn and delivers unbelievable power. Honestly, it's very hard to describe just how loud these horns are. If you want a real train horn, this is the answer.