LT245/75R16 E 120/116R
The LT here signifies that it is a light truck tire. The difference between the PS and LT tire is that a LT tires are designed to carry heavy loads or for towing large trailers.
This is the category of pickup trucks, sport utility vehicles and full size vans that differ from the P metric tire that services all the same vehicles ½ ton and under. These tires give you substantial reserve weight carrying capacity to accept additional stresses that come along with carrying heavy cargo. All LT tires typically have more tread depth, larger load carrying capacity and extra plies than a P metric tire, because of this the speed rating on the tire is reduced. (See example below) The most air a tire can hold, the more weight it can support. This is why LT tires have more plys. With air pressures of up to 85psi, LT tires have the capacity to hold more.
Below in the example you see 120/116r… The 120 is the load index of a vehicle that has 4 tires (single) on it instead of 6 tires (Dual Tires on the back of vehicle) and the second number is the load index of a dual tire application. Notice that the load carrying capacity is less than a single tire application. The reduction in carrying capacity here is to withstand stresses experienced when a single tire goes flat on a dual tire application so the 3 remaining tires can temporarily handle the load at reduced speeds.
LT245/75R16 E 120/116R E (10 PLY) 120 (SINGLE 3086LBS) 116 (DUAL 2756 LBS) R(106 MPH)
P245/75R16 111T 111 (2403LBS) T (118 MPH)
You can see now why we have LT and P metric tires that are the same sizes but differ in every way from what they were intended to be used on and for.