The Boeing 737 Next Generation (737 NG) took the popular Boeing 737 series to new heights. And though the nose tyre for the 737 NG remained the same size at 27x7.75-15 (DR25821T) as the tire used on the 737 classics the main gear tire increased in size to a H44x16.5-21 (DR29622T). This is a bigger tire and a bigger wheel. This H44.5 tire, when used on the Boeing 737 NG is rated to 225mph and has a ply rating of 28.
The growth in the size of the aircraft tire for the Boeing 737 NG was due to the increasing size of the airplane and its consequential weight gain. Larger tires can hold more nitrogen; the gas which supports the load of the aircraft. Bigger aircraft generally require either bigger aircraft tires or more of them. The Boeing 737 Classic series and the Boeing 737NG series of airplanes both deploy two nose landing gear tires and four main landing gear tires.
The Dunlop tire for the Boeing 737NG are designed to be robust and dependable; exactly what is needed for this workhorse of the skies.