64 to the downhole environment through dump port 66 the hydraulic fluid may be input to the chamber 64 through fill hole 68 after the chamber 64 is filled hole 68 is closed off by check valve 70 and with a backup plug as shown in fig6 housing 43 as shown in fig3 is fixedly connected to housing sub 42 by hex head screws 45 and serves as an actuating tool housing coil spring 74 is compressed when the chamber 64 is filled with pressurized fluid and thus biases piston 76 upward piston 76 is sealed to the lower portion of the housing 43 by 0 ring 78 and upward movement of the piston 76 is prevented since the chamber 64 is sealed until the coil assembly 62 is activated and since the fluid within the chamber 64 is for practical purposes incompressible rod 80 is fixed at its upper end to the piston 76 and extends through the retainer ring 82 and then through the latch sub 72 ring 82 includes a threaded port 84 to receive the upper end of collet mechanism 86 and cooperates with the collet mechanism 86 to retain the rod 80 in its run in position or stop position as shown in fig3 i e before the setting tool is set the lower end 81 of rod 80 thus engages a plurality of finger collets 86 which are housed within the plug latch tube upper end 95 of the.