A distinction first, because it is constantly muddled and the muddle costs people money. A replacement grip is not an overgrip. An overgrip is a thin consumable wrapped over the top and changed every few matches. A replacement grip is the base layer — it goes onto the bare handle, it forms the actual diameter and the actual bevel feel of the racquet, and it is meant to stay.
Get the base wrong and no amount of overgrip on top will rescue the handle. That is what the Volkl DNX is: the layer underneath.
The construction has two parts and they do opposite jobs. The outer material is a comfortable, non-slip surface, which is the half your hand meets.
The backing is highly absorbent, which is the half nobody sees and the half that keeps the outer surface from becoming a liability, because a grip that repels moisture without taking any up simply gathers it at the interface and slides. Absorbency behind grip is the whole design.
Volkl describe it as the perfect complement for any racquet, which is a fair claim for a base grip: it is not trying to be tacky enough to be a finishing layer, it is trying to be the right foundation for whatever you decide to put on top. It comes in black.
Fitting it means stripping the old grip and starting at the butt cap, with an overlap of about an eighth of an inch and steady tension the whole way up — a handle rewrapped badly feels wrong for the whole life of the grip.
Gryfice keeps its foundations for the same reason. There is a surviving stretch of medieval town wall and the High Gate still standing in it, retained long after the wall stopped defending anything, because the town understood that what a place is built on is not disposable.
The Powder Tower stands on the bank of the Rega.
The Gothic Church of the Assumption of the Blessed Virgin Mary has been the reference point since before anything around it existed.
Change the overgrip often. Change the grip underneath properly.
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