The San Diego Chargers wore their powder blue alternate uniforms on Sunday. As you know, one of the sports world's most iron-clad rules states that whenever this uniform is worn, countless fans will respond by saying: They should go back to wearing their original powder blues from the 1960s. Those were the best football uniforms ever!

And those fans are right -- mostly. The Chargers' original powder blues were gorgeous. What many fans don't realize, though, is that the team's original powder blue period, which ran from 1960 through 1973, actually featured a surprisingly large number of variations, with many of the uniform's key elements -- the helmet, the pants, and even the shade of blue used on the jerseys -- in constant flux. So when people talk about the Chargers' "original powder blues," they're actually referring to a wider range of uniforms than they probably realize.

Let's look at some of those variations, one uniform element at a time:

1. The shade of blue. The Chargers actually used four different blue tones from 1960 through 1973. All of them looked pretty good, but only the final one, in use from 1968 through '73, could be described as a true powder blue.

Chagers' original powder blue era actually included 4 different shades of blue. Only the last one was a true powder (h/t @GridironUniform). pic.twitter.com/MIkqoPUIzh — Paul Lukas (@UniWatch) November 7, 2016

The color that the team uses for its current powder blue alternates -- the uniform set worn this past Sunday -- is lighter than any of those original shades of blue.

2. The helmet bolts. The lightning bolts on the Chargers' helmets have always been gold, right? Wrong. The bolts were blue for the team's inaugural season in 1960 (and so were the bolts on the blue jersey that year). After changing to gold in 1961, the helmet bolts were blue again in 1966 (but the bolts on the blue jersey stayed gold that time around).

Lightning bolts on Chargers' helmet & jersey were blue in 1960, then turned gold in '61. Blue reappeared on helmet (but not jersey) in '66. pic.twitter.com/xvZWA30zqi — Paul Lukas (@UniWatch) November 7, 2016

3. The pants. When you think of the Chargers' powder blue era, which pants do you instinctively envision them wearing? It's a trickier question than you might think, because the Chargers wore four different pant designs from 1960 through 1973: white with blue lightning bolts down the sides; white with gold bolts; gold with blue bolts; and gold with conventional striping.

Chargers used four different pant designs from 1960 through 1973. pic.twitter.com/rg3m1OXSsp — Paul Lukas (@UniWatch) November 7, 2016

The reality, of course, is that all of these uniform combinations looked good on the field (and so did their assorted white-jerseyed counterparts, for that matter), so you could mix and match just about any of these elements and it would still turn out fine. Still, it's interesting to see just how much variety there was in such a short time period.

Meanwhile, there's one other detail from the Chargers' early days that's worth mentioning: In 1962, San Diego was among the recipients of the All-America City Award, a civic honor bestowed annually on 10 communities around the nation. The Chargers responded to this by wearing a commemorative decal on the crown of their helmets in 1963.

Good look at the "All-America City" decal that the Chargers wore in 1963. pic.twitter.com/KQLbrQet8s — Paul Lukas (@UniWatch) November 7, 2016

Serious attention to detail: Including the Chargers' 1963 "All-America City" decal on an electric football player! pic.twitter.com/FpCybP8QZ6 — Paul Lukas (@UniWatch) November 7, 2016

That decal has never been included on a Chargers throwback uni. Wouldn't it be cool to see it on the field again? Hey, team owner Alex Spanos: Make it happen, cap'n.

(Special thanks to William Schaefer of the Gridiron Uniform Database for his research assistance.)

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Paul Lukas wishes the Chargers would restore the uniform numbers to the sides of their helmets. If you like this column, you'll probably like his Uni Watch Blog, plus you can follow him on Twitter and Facebook. Want to learn about his Uni Watch Membership Program, be added to his mailing list so you'll always know when a new column has been posted or just ask him a question? Contact him here.