treating of the formation zone 18 the pumping of fracturing or treating fluid from the earth 39 s surface may be discontinued and the straddle tool 10 may be operated to dump any excess fluid thereby relieving the pressure in the straddled interval 30 in general the packer cups 26 may be configured to seal against extreme differential pressure the packer cups 26 may also be flexible such that it may be run into a well without becoming stuck and durable so that high differential pressure may be held without extrusion or rupture as such the packer cups 26 may be constructed from strong and tear resistant rubber materials examples of such materials may include nitrile viton hydrogenated nitrile natural rubber aflas and urethane or polyurethane fig2 illustrates a cross sectional view of a packer cup system 200 in accordance with one implementation of various technologies described herein the packer cup system 200 may include a packer cup 226 having a metal support 220 attached thereto both the packer cup 226 and the metal support 220 may be coupled to the mandrel 50 in one implementation the packer cup system 200 may include a backup component 210 having a rubber ring 240 coupled to the metal support 220 in another implementation the rubber ring 240 may be supported by a support member 250 coupled to the mandrel 50 the rubber ring 240 may be made from strong and.