Aside from the possibility of intentionally sending the wrong parts, it is also possible that the units that measured 300Pf were really 270 Pf devices with 10% tolerance, all found on the plus side, 270Pf +27Pf =297 Pf, fairly close to 300. So they should have been marked 271 instead of 270. Also likely that somebody found a batch of 270Pf devices marked with the complete value instead of 2 digits and a multiplier. I have run into that and it is a pain. I think that it comes from unknowing purchasing people.
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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