valve body 11 the upper side is held firmly against the annular groove 16 and the back portion 4 of the substantial y shape is disposed so as to face the high pressure side 14 thus by incorporating the annular packing 3 having the substantially y shaped cross section of the present invention into a capacity control solenoid valve impurities can be prevented from entering into the minuscule gap between the valve body and the valve housing without enlarging the capacity control solenoid valve and as a result there is no need to increase the thrust of the solenoid fig5 and 6 are front cross sectional views for describing a case in which the annular packing 3 having the substantially y shaped cross section of the present invention is mounted in a capacity control solenoid valve for example wherein the same symbols shown in fig4 indicate the same components in this example between the valve body 11 and the valve housing 12 a diameter enlarging part 17 for mounting the annular packing 3 is provided to the inside surface of the valve housing 12 in the narrow area 15 between the low pressure side 13 and the high pressure side 14 this diameter enlarging part 17 is shaped such that its left side is connected to the narrow area 15 while is right side is open as shown in fig6 to mount the annular packing 3 as shown in fig5 the annular packing 3 is disposed so that the back portion of the substantial y shape faces the high pressure side 14 the left side of the.