Yes, based on the wide frame leg, it is a first generation Summit. It would be nice if you could redeem the inserts and just have to replace only the casters. But, I think with some searching you can find the inserts, too. Now, on some other parts on these wonderful old Summits, you have your work cut out for you. And, as has been mentioned on this board many times, look carefully at the front of your firebox - the part made out of porcelain plated steel where the burners go in. This is notorious for rusting around the burner openings and in time becoming a dangerous situation as fire can blow back out. No easy fix here. I am working toward getting my 450 disassembled and taking the part to some sheet metal shops to come up with potential solutions. I will definitely post a new thread if I can come up with something viable.