Not cheap, but well woth it. - SureFire Shotgun Forend Weapon Light

I received the exact light pictured. Surefire is expensive, but also the very best. Used by military and LE around the world. It will withstand a lifetime of anything the user encounters. Fit and finish was excellent. Surefire provides the tool to remove the old forend and install this one. For the Mossberg line, all you need to supply is a small punch. Was a 5 min job to put it on my 590 Shockwave. It is a flamethrower of pure white light. Not sure about battery life (still on the original set) , especially a 600L output, but if you can afford a 350.00 light, its a safe bet you can afford a few batteries. Adds some weight and a little bulk, but its not a bad thing on the little Shockwave shooting buck/slugs.