Review on WOHHOM 100A/150A Audio Circuit Breaker Auto Car Stereo Inline Fuse Holders Inverter, Manual Reset 12V-24V DC for Automotive Marine Boat Audio System Protection by Elmito Yeager

Much better than the built in fuse. You will NEVER need to buy another fuse as there is NO fuse in it. Also, you can turn off your amp if you need to adjust the cross. - more sound settings for your mid and high speakers. My subwoofer is a 15 year old Infinity BassLink. And I'm running it with a Pioneer AVH NEX-2550 head unit. My stuff is BANGIN' HARD now. This is because the 30 watt fuse I originally had under the hood was weak and was restricting proper flow in my amp. My 15 year old subwoofer sounds sooooooooooooooooooooo much better with this breaker. I never thought it could fuck so well. And it sounds cleaner.=========== INSTALLATION was easy.1) - Unhook only the positive wire and place the clip on a cloth so it doesn't accidentally touch the metal2) - Remove about 1/ 2 inch of the audio cable's protective sleeve on both ends that go into the fuse switch3) - Insert the wire fully into both ends of the switch4) - Screw the wire cables tight with a hex wrench.5) - Make sure the transparent ones and red protective caps are screwed watertight6) - NEVER install this switch near the amplifier. You just need to install it as close to the car battery as possible. About 6 inches of cable or so. 7) - For SAFETY PURPOSES, I made sure the switch was in the "OPEN" position BEFORE I connected it to the battery terminal. 8) - Connected to the battery terminal. Car and radio on.9) - Switch closed10) - Alto All done son !=========== ADDITIONAL NOTES: I got 40 AMP for my 200 watt amp. Make sure you are purchasing the exact power amp that is SAFE to match the specific power of your amp. A NOTICE. Buying too much amplifier for the switch amounts to a complete lack of protection. Hope this all helps.