The cargo trucks criss-crossing India are brash, psychedelic folk art. They're covered from bumper to bumper in religious iconography, talismans, and all manner of elaborate motifs, prompting the men behind their wheels to affectionately call them their "painted ladies."

Photographer Dan Eckstein traveled some 10,000 kilometers through the country and trained his camera on this slice of Indian life for his book, Horn Please, to be released in December.

“India is beautiful and colorful and a wonderful place to make photographs, but I think it’s a hard place to make unique photographs—something that’s not an exotic cliché,” said Eckstein.

He explored the region for six weeks accompanied by a driver and translator, spending much of his time in truck stops, mechanic depots, and places you won’t find in the Lonely Planet.

"With a lot of the truck drivers there's a little bit of machismo,” said Eckstein. “They're smoking cigarettes, chewing tobacco, and listening to their music. There's a feeling of adventure and the open road.”

The drivers had a bit of swagger and were quite serious when he made their portraits, but that melted away as soon as they saw their photos on the back of his camera. Then they were all smiles.

The trucks are drivers' homes for weeks at a time while they haul goods all over the country. They work in teams of two or three, driving in shifts, taking turns sleeping in bunks, and having meals at simple truck stops along the way.

Horn Please: The Decorated Trucks of India , powerHouse Books 2014.

Whether Hindu, Muslim, Sikh, or Christian—there’s usually ample evidence by the illustrations on the tailgate, sides, and the shrines installed in the cabs. If a driver is from the north, his good luck garlands may include chiles and limes. If he’s from the south, conch shells replace the chiles. Talismans against the evil eye include devilish faces or the image of a shoe, all carefully hand-painted.

Spend any time on Indian roads and you see why so many drivers seek the protection of good luck symbols.

"It's a little hectic," Eckstein said. "There's every kind of vehicle—ox-drawn carts, shepherds bringing flocks through the highway, and cows wandering around. People don't stick to one lane or another."

The trucks are bold expressions of individuality and repositories of masculine, laboring pride. Drivers treat their rigs as evolving works of art, periodically commissioning a new illustration from roadside artists like one might collect tattoos.

The title Horn Please was inspired by the ubiquitous request painted in stylized lettering on the back of nearly every cargo vehicle. The many variations of the phrase encourage car drivers to sound their horn in alert when they plan to pass a truck, though Eckstein claims no encouragement is necessary.

"In India, the horn is going constantly to let everyone know where you are and where you’re going,” he says. “It’s an essential tool for navigating the road.”