Compatible with mid-sized engines 125cc-250cc 2-strokes or 4-strokes engines, GY6 engines. Compatible with most carburetors (PZ24 150cc and PZ30 CG 250cc etc) requiring a 42mm (1.65in) inside diameter opening. Package include: 1 Ignition Coil, 1 Spark Plug Aftermarket Product with Premium Quality. Product description Inlet diameter: Approx. 42mm / 1.65 inches. Size: approx. 121 x 72 x 72mm / 4.76 x 2.84 x 2.84inch. Compatible with mid-sized engines 125cc-250cc 2-strokes or 4-strokes engines, GY6 engines. Compatible with most carburetors (PZ24 150cc and PZ30 CG 250cc etc) requiring a 42mm (1.65in) inside diameter opening. Compatible with: CB650 1979-1980 Compatible with Kawasaki: KH400 (2 stroke)1976-1978 KZ440 1980-1983 KZ900A 1976-1977 Z1 /A/B-900 1973-1975 KZ1000 1977-1980 Compatible with Suzuki: GT380/GT550 1977-1979 GS750, GS1000 1977-1979 Compatible with Yamaha: RD250, RD350 1973-1975 RD400 1976-1978 Please check the model number carefully be