UPS is adding another 50 electric delivery trucks to its "rolling laboratory" fleet of alternative fuel and advanced technology vehicles.

But Sandy Springs-based UPS has had decades of experience with electric trucks, pre-dating the latest resurgence of electric vehicles. Here's what UPS electric trucks looked like in the 1930s, 1980s and today.

A Walker Electric UPS Package Car circa 1935. Walker was a manufacturer of electric vehicles. Source: UPS
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UPS paired up with the University of Alabama to road test this fully electric vehicle in 1980. Source: UPS
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A Modec fully electric vehicle used in London, circa 2009.  Source: UPS
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A 2009 UPS electric car rendering. Source: UPS.
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A 2018 rendering of the new UPS plug-in electric delivery truck. Source: UPS
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