Lutz had the special size o-ring my production line needed. I inquired with a dozen other o-ring suppliers; Lutz responded first, had the lowest price, and shortest lead time. Lutz took my o-ring prints and helped select the right material (we were going for a low-performance FKM, but they suggested a Viton compound that was cheaper than the FKM).
Pros: fast response times; you get to talk to a dedicated account rep. every time; pretty cheap vs. the ""bigger dogs""
Cons: no online pricing (except for some liquidation stock that we didn't need)
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