I know that Colorado does this as well. Probably other states in the USA do too. https://www.codot.gov/programs/speedenforcement
MellowBright
joined 3 years ago
A shotgun shell. It's a fairly common practice to reload shotgun shells with rock salt as a cheap, less lethal ammo. https://www.youtube.com/watch?v=5BY_sD3MvTY
There's signs posted in advance that say something along the lines of "Speed Enforcement Camera Ahead". The only reason they'd be a surprise is if you're not paying attention to signage. They're in the mountains, but I've mostly seen them out in the flat eastern parts of Colorado where the roads are mostly long straight stretches over flat terrain. Which makes sense, since that's where it's easy to speed.