embodiment two upper connector wires 40 per flattened distal peak portion 36 are illustrated however any number of upper connector wires 40 may be secured i e welded to each flattened distal peak portion 36 of each support wire 28 the distal valley portions 38 of the support wires 28 may be stapled or otherwise attached to the transverse slats 14 which are in turn affixed to the base frame 13 if desired additional steel end wires not shown may be added either before or after the stackable spring assembly 16 has reached its final assembly destination these end wires have spaced ends which are crimped around the border wire 22 and the endmost upper connector wire 40 respectively these end wires provide additional stiffness to the stackable assembly 16 in an edgemost location of the ends of the assembly 16 so as to prevent the end border wires from deflecting and being permanently distorted when a person sits on the end of a bed of which the foundation forms a part such steel end wires are shown in u s pat no 5 361 434 which is hereby incorporated by reference in its entirety referring again to fig1 continuous longitudinal wires 46 may be included in the stackable spring assembly 16 these longitudinal wires 46 have their ends 48 welded to and or crimped around the border wire ends 26 26 these longitudinal wires 46 may be welded along their lengths to the upper connector wires 40 as desired in the illustrated embodiment two longitudinal wires 46 per foundation 10 are illustrated however any number of longitudinal wires 46 may be incorporated into the foundation the nestably stackable spring assembly 16 of bedding foundation 10 is.