TENNIS.com gear editor Justin diFeliciantonio and his technical advisers answer your equipment questions each day. Click here to send in a question of your own.
I've always been confused about how synthetic gut strings are different from multifilaments. Are they separate categories of strings? Is synthetic gut simply a cheaper multifilament? Clearing up the terminology would be very helpful.—Samuel
These terms really can get confusing, Samuel. Technically speaking, “synthetic gut” refers to a string made out of man-made fibers, specifically one that aims to imitate a natural product, i.e., natural gut. More practically, though, synthetic gut usually signifies a string that’s constructed out of nylon; in the tennis community, the term tends to connote cheaper manufacturing processes and lower prices.
“Multifilament” products, on the other hand, are generally pricier and higher grade. Multifilaments are still made of nylon, but they’re typically more elastic, and thus more powerful, than your run-of-the-mill synthetic gut. As U.S. Racquet Stringers Association explains,
“Elasticity refers to a strings ability to return to its original shape and condition after ball contact. Typically, elasticity will govern a string’s ability to return energy to the ball. Elongation is the measure of a string’s elasticity and is closely related to the power potential of a string. It also is a measure of a string’s ability to absorb incoming ball shock during impact. All things being equal, the greater a string’s elongation, the greater its ability to absorb incoming ball shock. Generally, multifilament strings with no center core have the greatest elongation of nylon strings. As a result of this characteristic, some multifilament strings lose tension faster than center core constructed strings.”