JBL Go 4 speaker holder to fit the back rack of an ebike. I designed it to fit my Heybike Mars 2.0, but it could fit others as well. It has slots for magnets and two ports for zip ties. 

Updated: 7/24/24 V2 rounded off all corners and got rid of the boxy look.

Updated: 12/22/24 V3 made some design changes but kept the original design so users can choose between the two.