Amplifier mounting brackets for stacking, bottom amp is held off the bottom to allow proper cooling, made from laser cut steel and powdercoated. These will save you from using flimsy all-thread and not having to drill out the mounting holes on those $2000+ amps. These are made to fit just about any amplifier, will fit most amps. Kit includes 4 brackets(2 left, 2 right) and mounting screws for amp to bracket Dimensions for the spacing and height 2 amp rack is 4.625" tall, bottom amp is 1.25" from the bottom, with 3.125" between the tabs. AMPLIFIERS NOT INCLUDED!!!!