28 a support cylinder 29 has fixedly and securedly positioned at upper and lowermost portions thereof a lower internally threaded nut 30 and an upper internally threaded nut 31 to receive the threaded section 28 whereupon rotation of the support rod 24 and associated threaded section 28 reciprocatably positions the support cylinder 29 along the length of threaded section 28 the support cylinder 29 has fixedly secured at diametrically opposed sides thereof the respective first and second horizontal support arms 13 and 14 as illustrated in fig2 and 4 it may therefore be appreciated that as the support cylinder is vertically positionable along the threaded section the support arms 13 and 14 with the associated backboard 12 and frame and net organization 11 are also reciprocated therewith attention to fig5 illustrates a modification including an elongate enclosing first and second respective resilient sealing flaps 32 and 33 enclosing the associated first and second elongate slots 19 and 20 formed within a further support channel 117 the sealing flaps 32 and 33 are formed with a central slit to receive the associated support arms 13 and 14 respectively therethrough to prevent intrusion of airborne contaminant from entering the bearing and associated mechanism of the adjustment mechanism of the apparatus as to the manner of usage and operation of the instant invention therefore the same should be apparent from the above description and accordingly no further discussion relative to the manner of usage and operation of the instant invention shall be provided with respect to the above description then it is to be realized that the optimum.