What MightyMount do I use with the CoreBar or JetStream Bar? Dave Dezellem Updated January 10, 2018 00:51 Follow The MightyMount 39H is what you will need to fit non-Universal accessories to your Core or JetStream bars. Related articles CrossBar Options The CrossBars that Yakima recommended for my vehicle seem really long. Can I cut them down to length? My car came with a factory rack or Aero style bars, what mounts will work? What is SmartFill? CrossBar Weight Limits Comments 0 comments Article is closed for comments.