Beyond experimenting with raw materials to create ‘new-and-improved’ racquets that would appeal to professional and recreational players alike, the next innovation that drastically changed the look, feel, and design of the tennis racquet revolved around the size of the racquet—especially the head.
Previously, the hitting surface of racquets were all of “standard” size—namely in the approximately 60-70 square inches range. In the 1970s oversized racquets with a head size of 105+ square inches (677+ square centimeters) and midsize racquets with a head size of 85-95 square inches (548-613 square centimeters) were invented and introduced to global tennis scene.
In today's market, besides the oversize and midsize racquets, there are also options for midsize plus racquets (95-105 square inches or 613-677 square centimeters) and super-oversize racquets (116+ square inches or 748+ square centimeters).
However, there is a limit to how large a racquet can be. In 1981, the International Tennis Federation (ITF) first established the official rules for racquet sizes. The present rule reads that a racquet "shall not exceed 73.7 cm (29.0 inches) in overall length and 31.7cm (12.5 inches) in overall width. The hitting surface shall not exceed 39.4 cm (15.5 inches) in overall length...and 29.2 cm (11.5 inches) in overall width."