Berry was famous for his attention to detail and preparation, which he used to overcome his physical limitations. Considered slow for a wide receiver, he ran the 40-yard dash in 4.8 seconds. Rather than speed, he was renowned for his precise pass patterns and sure hands; he rarely dropped passes, and he fumbled only once in his career. He would squeeze Silly Putty constantly to strengthen his hands. He and Unitas regularly worked after practice and developed the timing and knowledge of each other's abilities that made each more effective. The reason for this, according to Berry, was that the two did not think on the same wavelength. "Every season we had to start all over on our timing, especially the long ball," said Berry. "He knew he had to release the ball when I was eighteen yards from scrimmage for me to receive it thirty-eight yards out. I knew I had to make my break in those first eighteen yards and get free within 2.8 seconds." He also relied on shifty moves, and by his count, he had 88 different moves to get open, all of which he practiced every week.