Polyester/Monofilament strings are constructed with a single polyester fibre and a thin coating, they are produced in different gauges which can enhance different playing techniques such as topspin. This type of string is extremely popular with tennis professionals as they provide the optimum level of power, control and spin.

Polyester strings would not suit every player. The last of elasticity and stiffer feel provides less comfort and may hurt the arm over time. They tend to lose tension very quickly in comparison with other types of string which results in loss of control so your racket my need to be restrung more frequently.

Polyester/Monofilament pros:

Extremely durable
Well priced
Produced in different gauges
Can provide optimum level of power, control and spin

Polyester/Monofilament cons:

Not suitable for players wanting comfort due to lack of elasticity
Loses tension quickly