second cylindrical cavity similar to 101 on its posterior vertical face to allow routing of fluid between the two blocks a cylindrical flow element 62 is used to route fluid between the blocks refer also to fig8 containing isometric view 62 a side view 62 b and cutout view 62 c of cylindrical flow element 62 fluid flows through fluid passage 78 from a first block 100 in fig3 to a second block 100 in fig3 seals 205 are placed on feature 71 at both ends of cylindrical flow element 62 to keep fluid from leaking from the interconnection dowell pins 212 are used in conjunction with holes 112 and retaining groove 73 in cylindrical flow element 62 using passages internal to block 100 fluid is routed in and out of components 240 and 220 by means of ports 105 seals 204 are used to form a hermetic connection with components preventing fluid from leaking into the environment refer to fig4 containing isometric view 110 a side view 100 b and cutout view 100 c of block 100 the front and back vertical faces of this block 100 contain cylindrical cavities 101 designed to mate with cylindrical flow element 62 as described previously fluid passages 109 a and 109 b route fluid to interconnect port 105 designed to accept and retain seals 204 fig5 illustrates the details of port 105 an important aspect of the invention is the capability to accept and retain seals 204 in order to facilitate mounting of various components particularly when the fluid control system is mounted vertically.