T Slot bolts for rhino rack crossbars

Im having a hard time finding information about what i actually need. I just put some votex cross bars on my shell, and im needing some eye bots or something to tie to. They have T slots, but are there different sizes? id like to put about 3 eyes on each bar to tie down 2 kayaks up top. where can i find something i know will fit? yeah i can go on Amazon and order something, but i dont know if it will fit, and if its something i can just go to a hardware store and pick up, then ill just do that. thanks

 

hey bro i had the same problem, it was a pain & theyre EXPENSIVE when you find them. I went to home depot got a flat washer and apropriate length bolt, you might need to grind of a lil of the washer. Tap weld em on or jb weld em like me.