Well, I won't go so far as to say that they are a racket, but....... they are not a non-profit organization. They have a bad reputation because of their poor customer service, yet if you pay them extra money for expedited testing you can still get the testing you need completed on schedule.
Some engineer colleagues of mine say that UL is a racket. They have toured some of their facilities, and found their practices and testing areas to be very unprofessional and ineffective. Once a company set out to protect consumers, now is just a company to absorb as much money as they can.
After hearing the stories, I have to pause and question any UL standard.
Linear guides are one of the most important components required for the design of automated or computer-controlled equipment. Aluminum profile extrusions, used for these guides, can enable designed-in functional features.
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