I purchased a one month old Kaymar bar from Barry (Redback) a while ago and it didn't come with the corner posts that go up under the tail lights, when I ordered them from Kaymar they wanted to know if it was for a 3 or 4 because they are different. So I'm guessing a bar for a 4 won't fit a 3 and vice versa, for anyone looking at buying a second hand one might be best to check with Kaymar first to see if they are interchangeable between models.
Not sure why I bought it actually after all the hassle buying the new corner posts which for some reason took ages and cost $400 I decided not to fit the bloody thing so it now sits on the floor in the garage taking up space. ... :angel:

