13" RESONANT DRUM HEAD MADE USING A SINGLE PLY OF 10MIL FILM. A SINGLE PLY OFFERS AN OPEN AND EXPRESSIVE SOUND. A SINGLE PLY OFFERS AN OPEN AND EXPRESSIVE SOUND. SOUND SHAPING TECHNOLOGY INSURES OPTIMIZED PERFORMANCE FOR EACH INDIVIDUALLY SIZED DRUM HEAD. EXCLUSIVE LEVEL 360 TECHNOLOGY COLLAR DESIGN ENSURES PROPER CONTACT BETWEEN DRUM HEAD AND DRUM SHELL.