Size of Guard coil: M7.14: 9 9 4mm; M9.53: 12 12 4mm; M12.07: 16 16 6mm; M15.88: 19 19 6mm; M19.05: 23 23 6mm; M22.23: 27 27 7mm; M25.4:30 30 8mm. Multiple Sizes Available: There are 2 different coils, 12 different sizes.
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