mounting bracket 90 of the present invention is designed to couple a working device such as a hammer to the end of a boom for easier adjustment and use than heretofore available fig1 3 for illustration purposes only the mounting bracket 90 will be discussed in connection with securing a fluid driven hammer to the boom of a backhoe nonetheless a mounting bracket in accordance with the present invention could be used in connection with a wide variety of other working devices and carriers in the preferred construction mounting bracket 90 includes a base plate 92 a pair of mounting flanges 94 extending from a first side 96 of plate 92 in one direction and a pair of mounting ears 98 extending from a second side 99 of plate 92 in an opposite direction mounting flanges 94 are spaced to receive the sides of the stick 44 and brace 73 of boom 40 each mounting flange 94 defines a pair of spaced apart holes 101 103 adapted to be aligned with corresponding holes not shown in the stick 44 and brace 73 respectively pins 105 are received into the aligned holes to movably couple mounting bracket 90 to the end of boom 40 in like manner ears 98 are spaced to receive therebetween a pair of side plates 107 which are welded or otherwise attached to the sides of casing.