There are seven widths of R-Bar and eight S-Bars. The silver XXW is not available in the R-Bar.

  XXW (S-Bar only)   XW/XXW   XW   W/XW
  W   M/W   M   N/M
Gullet Change Step 1
Step 1: Use the hex key to remove the 2 screws at the front of each panel.
Gullet Change Step 2
Step 2: Slide the panel off the point of the tree.
Gullet Change Step 3
Step 3: Unscrew all 4 bolts in the gullet bar and remove the gullet bar.
Gullet Change Step 4
Step 4: Insert different width of gullet bar. Insert all 4 bolts by hand then secure.