Don't know for the Texas Edition, (which looks like maybe you have), but they were stock on the Off Road Pkg.
They're junk and should be replaced after 10K to 20K miles. They have cellular foam inside to separate the oil from the air, and it breaks down quickly, and then the hydraulic damping of the fluid is hosed.
If they are OEM instead of aftermarket, they will have a hard plastic imitation dust boot on the rear ones, that slides over the shock's body instead of compressing like an accordion. That probably reduced Nissan's cost buy $1.