Leaf Springs are nowadays most commonly used on full size pickups. Where many vehicles previously used leaf springs, auto makers have seemed to change over to coil spring suspension for most lighter vehicles for improved ride quality. Although they do not support as much load, most drivers can sacrifice the weight capacity for the ride quality.
A leaf spring is secured to the vehicle with spring eye bolts attached to a shackle as well as strapped to the axle via use of u-bolts. The load support mechanisms will come in a variety of sizes and amount of leaves, from single leaf or "mono leaf" springs to heavy duty springs upwards of 12 leaves and thousands of pounds.
Another leaf spring related product is an add a leaf. An add a leaf, or "extra leaf" is an additional piece of steel that can be added to your existing spring to achieve a greater ride height or load apacity.