Originally Posted by m3an
bump for OP;
yes they should be 2.5 diam; IMO these look like Vibrant brand, so you can look up specifici specs there and I would be hard pressed to believe Challenge makes their own resonators.
+1. These look very similar to the Aero AR25 resonators minus the more conical ends. I paid 72 shipped for 2 aero resonators that look like these and have a cool etched/raised logo on them.
OP, you may want to drop the price just a little bit--I think more people will bite then.
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