I maybe wrong, won't be the first time, but I don't think it is possible to make a slide on or clip on type mirror that will not vibrate so badly at speed as to make it nearly useless. I tried them before, then used after market door mounted trailer mirrors and both vibrated badly. I now have Power Visions which hardly vibrates at all at full extension and no vibration at 3/4 or less. These mirrors will extend 6 inches, about 1. 5 inches more than the Magnas, although I think the extension of the Magnas would be more than adequate for towing. I normally use my mirrors at 2/3 extension and can see fine around my flatbed headboard. Those with standard pickup beds will see even better. These mirrors are not heated, but I don't need heated mirrors.
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1996 3500 Clubcab SLT, auto, 4. 10 limited-slip, TST #5, 370s, AFC spring kit, Psychotty, Dunrite converter, Trans-Go, DiPricol EGT, boost & trans temp. gauges, 9 ft. aluminum flatbed and tool boxes with Venco dump. Custom front bumper, Hadley air horn, PowerVision mirrors & 4" Stack Exhaust.