An end turn portion (12a) of a coil spring (12) includes a first portion (12a 1 ), a second portion (12a 2 ), and a third portion (12a 3 ). The first portion (12a 1 ) is always in contact with a spring seat irrespective of the magnitude of a load applied to the coil spring (12). The second portion (12a 2 ) contacts the spring seat when the load applied to the coil spring (12) is large, and is separated from the spring seat when the load is small. The third portion (12a 3 ) is always separated from the spring seat irrespective of the magnitude of the load. An insulating sheet (50) made of a material having rubber elasticity is attached to a lower surface of a wire (40) at the end turn portion (12a) by means of adhesive bonding. The insulating sheet (50) is provided on a lower surface of a region including at least the second portion (12a 2 ).