Rico Reserve Classic Alto Sax, Strength 3.0+, 10-pack Thicker blank for a more resonant sound Strength 3.0+, Filed cut, box of 10 reeds Filed for flexibility and fast response Like the Reserve line, uses only the densest, lower-internode cane for longer durability and consistency Offered in strengths 2.0 to 4.5, including a special 3.0+ strength