Distance between installation center hole : 80mm Primary resistance 1.8 The secondary resistance with the cap: 36K(the secondary resistance without the cap: 26K) Name:ignition coils with spark plug caps Type:Ignition coil Part Number: Ignition Coil Part Numbe: 30510-MM8-003 Spark Plug cap Part Numbe: 30701-MF5-000 30751-MR1-000 30753-MR1-000 This Accessories fits the following models: For Shadow VLX 600 VT600C 1988-2007, For Shadow VLX 600 VT600CD Deluxe 1993-2007 primary winding copper wire (full copper): 250 rounds Secondary winding copper wire (full copper): 28000 rounds The material of The iron core: silicon steel sheet Function: rust-proof, magnetic conductivity, low loss The material of the hat: silicone Function: high temperature resistance, aging resistance, insulation resistance The hat contains 1 resistor Function:to prevent short circuit Green plug for positive ,black plug for negative Colour:black Material:plastic Package Contents: 2 x ignition coils with spark plug caps Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.