The ZyMax Fire family of badminton strings features a BETA Polymer ZyWeaVe core encapsulated with a high tenacity BETA Polymer microfilament wear surface Download a ZyMax 62 & 69 Fire Catalogue Page Download a ZyMax 66 Fire & 66 Fire Power Catalogue Page REPULSION POWER: CONTROL: TENSION STABILITY: DURABILITY: REPULSION POWER: CONTROL: TENSION STABILITY: DURABILITY: REPULSION POWER: CONTROL: TENSION STABILITY: DURABILITY: REPULSION POWER: CONTROL: TENSION STABILITY: DURABILITY: FEATURES ADVANTAGES SPECIFICATIONS Material Proprietary BETA Polymer ZyWeaVeTM Core Proprietary BETA Polymer Microfilaments Gauge ZyMax 62 Fire (0.62 mm) ZyMax 66 Fire (0.66 mm) ZyMax 66 Fire Power (0.66 mm) ZyMax 69 (0.69 mm) Length  33 ft (10 m) set / 660 ft (200 m) reel Colors "Fire" Orange, Ivory White BETA Polymer Technology provides maximum dynamic stiffness and repulsion ZyWeaVeTM core prevents tension loss and maximizes strength and durability ZyMax 62 Fire: Ultimate Repulsion ZyMax 66 Fire: Ultimate Precision ZyMax 66 Fire Power: Ultimate Power ZyMax 69 Fire: Ultimate Strength Usage: Professional and amateur players For optimum repulsion, power and shot making For minimum tension loss and maximum strength and durability Stringing tension: ZyMax 62 Fire: up to 30 lbs (13.5 kgs) ZyMax 66 Fire: up to 35 lbs (16 kgs) ZyMax 66 Fire Power: up to 35 lbs (16 kgs) ZyMax 69: up to 40 lbs (18 kgs)