Cooper Discoverer STT PRO 35x13,5x20 121Q

The Cooper Discoverer STT PRO off-road tire was introduced by the North American manufacturer in the summer of 2015. What distinguishes this model from all other representatives of this line is its excellent adaptability for operation, first and foremost, off-road, for which it was created. At the same time, the North American company used almost all the latest technological developments that appeared after decades of successful activity in this field.

Reinforced carcass

One of such technologies is ARMOR-TEK 3, which is a reinforced carcass. The figure "three" in the name indicates the number of steel cords used in the carcass design. It is for this reason that this model weighs a few kilograms more than most of its analogs. However, this is an extremely small price for the exceptional strength and reliability that it demonstrates even on the most difficult off-road terrain. The manufacturer claims a 50 percent reduction in the number of damages. Another advantage of the additional steel cord is even greater resistance of the tread to uneven wear, which significantly increases the duration of its service life, as well as reduced rolling resistance.

Tread pattern with alternating number of longitudinal ribs

The tread pattern is characterized by openness, which is expressed in the form of a large number of individual blocks distributed over several functional areas - the central part and the shoulder zones. They are arranged in such a way that when moving, they form an alternating number of longitudinal ribs. Due to the shortened shoulder blocks in the central part, two or three of them are formed. This design gives the tire increased stability and good handling on the highway, as well as improved passability on soils with high moisture content.

Increased softness on the move

In addition to acoustic comfort, the North American tire manufacturers paid a lot of attention to ensuring good softness of the ride when developing this model. For these purposes, special zigzag-shaped lamellas were used. Due to them, the tread blocks deform in a certain way, thereby absorbing a large part of the impact effect from the irregularities on the surface of the road. Moreover, these same lamellas, when moving on slippery smooth surfaces, form a multitude of additional edges, improving traction with it.

Open design of the shoulder zones

The above-mentioned design features allowed the company's specialists, without fear for comfort and other operational properties, to give the shoulder zones a maximally open design. They are characterized not so much by the presence of numerous blocks, but by their large width and significant distance between them. Thanks to this, the Cooper Discoverer STT PRO tire demonstrates confident behavior when overcoming the most difficult off-road sections. At the same time, special asymmetric notches on the side walls of the blocks additionally increase the passability on soil surfaces with reduced bearing capacity.

Additional traction edges on the sidewalls

A significant part of the tread pattern is located on the sidewalls of the tires. The blocks located on them provide additional traction on sandy and earthy soils. Moreover, they give the tire even more efficiency when operated in a deflated state, which significantly improves performance on off-road terrain.

Reinforced bead construction

The excellent reliability of this model on off-road terrain is ensured not only by the three-layer steel cord, but also by the optimized construction of its bead. The North American tire manufacturers gave this part of the tire such a shape that the likelihood of damage to the bead, as well as the tire itself and the wheel disc, is minimized.

At the same time, its reinforced construction provides a more dense fixation of the tire to the wheel disc. This feature significantly improves the traction properties, and also allows the tire to be used in a deflated state.

Main features of the Cooper Discoverer STT PRO tire

- a three-layer steel cord provides a 50 percent increase in reliability when operating on off-road terrain, increases the resistance of the tread to uneven wear;
- low noise level, thanks to the alternating number of longitudinal tread ribs and the multi-step arrangement of blocks;
- special zigzag-shaped grooves give the tire additional softness on the move;
- open design of the shoulder zones, containing many wide blocks, improves passability on soil surfaces with reduced bearing capacity;
- special asymmetric notches on the side walls of the shoulder blocks increase traction on sandy and earthy soils with high moisture content;
- additional blocks on the sidewalls of the tire improve passability on sand and in mud;
- optimized shape and reinforced construction of the bead provide reliable protection for both the tire and the wheel disc from damage, as well as more dense adhesion of them to each other, which improves handling.