This is a new style of mount for all the round deeper start fish Finder sonar. You can mount the back plate anywhere then slide on your bracket twist the thumb screw to lock bracket to Plate and place your deeper where ever it needs to be this is for the bracket screws wipe cleaning cloth only not the sonar The item is 3-D printed accept the part that you manipulate the bar is covered in a super strong Gator sleeve to prevent any glare from centre bar Also looks pretty cool with the gator sleeve.