also includes an upper electrode receiving aperture 1066 configured to receive a top portion 1034 of l shaped electrode 1030 and an end portion 1052 of a power lead 1050 as shown in fig1 and 12 upper electrode receiving aperture 1066 includes a rectangular portion 1067 intersecting upper mating surface 1062 and a tapered portion 1068 intersecting an upper surface 1022 b of bumper 1022 referring to fig1 and 14 16 lower bumper portion 1070 includes tissue contacting surface 1022 a and a lower mating surface 1072 lower bumper portion 1070 also includes a substantially round projection receiving hole 1074 for receiving projection 1064 of upper bumper portion 1060 hole 1074 includes a tapered section 1075 that tapers from a larger diameter at a point near tissue contacting surface 1022 a to a smaller diameter approximately halfway through hole 1074 hole 1074 also includes a constant diameter section 1076 that extends from the point halfway through the hole 1076 to lower mating surface 1072 as discussed below lower bumper portion 1070 also includes a lower electrode receiving aperture 1078 for receiving a lower portion 1032 of l shaped electrode 1030 bumper 1022 is assembled by passing nitinol wire 1040 through slot 1024 seating electrode 1030 as explained below and aligning upper mating surface 1062 of upper portion 1060 and lower mating surface 1072 of lower portion 1070 such that projection 1064 passes through projection receiving hole 1074 l shaped electrode 1030 is seated in electrode receiving apertures 1066 and 1078.