Replacement Mounting Hardware for Thule Summit Rooftop Cargo Box

Question:

I need replacement mounting hardware for a very old Thule Summit cargo box. There is a sticker inside the box that says serial number is EG 208121. hard for me to believe it is still in there. Looking at your site I think the proper kit might be # TH04998. My old carriage bolts are M6 x 75mm 3 inch, space between mounting holes is 100mm 4 inch. Please confirm this is the correct kit. Assuming it is the correct kit, what are the base plates that fit between the box and cross bars made out of? My old ones are a rusty mess. Similarly, what are the carriage bolts made from? Old ones so rusty I will need to cut them off. Attached a picture of the box....

asked by: Ken M

Expert Reply:

For your older Thule Summit Cargo Box, the correct mounting hardware kit is the QM3 Quick Mount Hardware # TH04997. This kit includes all of the needed mounting hardware to attach the Thule Summit to the crossbars on your vehicle's roof.

We do have a few of the parts available as separate items:
Quick On/Off Bracket # TH04973
Protector Pad # TH05001
Box Plate use # TH04998 which is a steel plate with black paint for corrosion resistance
Carriage Bolt # TH10403 is yellow zinc plated steel for corrosion resistance
Wingnut # TH04877
Tie-Down Bracket # TH10375