Ever find yourself on your bike, only to be cut off by some jerk who doesn’t think bikes belong on the road? Or maybe you’re slowed down by some peds hogging the bike path. While you could try and ring your little bicycle bell or squeeze your meek little horn, you’re much more likely to get their attention with the horns they use on a train or an 18-wheeler. That’s exactly what DIYer Chad Thoren (aka “The Chadster“) did with his bike.

The Chadster outfitted his bike with a large dual-trumpet horn from a train, connected up to a tank filled with compressed air. He says this produces much louder results than you get by just hooking up the horns to an air compressor, so I can only imagine how loud it really is. The video clip below gives you a sense of it, but I’m guessing that in person, it’s much more startling.

The rather simple build requires a cruiser in order to provide a large rack for holding the compressed air cylinder, along with some hose, bungee cords and duct tape. Chad provides instructions on how to build your own over on Instructables, but recommends that you only use it to give pedestrians a scare (and maybe a heart attack,) and not riding in vehicular traffic. Personally, the bigger problem I see is that the rider of the bike probably needs to wear earplugs when riding if they don’t want to go deaf.