f because the card is disposed in a reverse position from the correct orientation which is shown in fig5 in fig5 the card contacts 94 a 94 f are in close and complementary registration with the card reader contacts 98 a 98 f unequal spacing of the card contacts at the ends of the card provide for correct installation orientation the card 90 may be a variety of shapes as viewed on a plane perpendicular to the axis which is the cross section taken along line 6 6 of fig5 such shapes are shapes other than planar and include but are not limited to shapes that are substantially circles 102 ellipses 104 and rectangles 106 as shown in fig6 a 6 b and 6 c respectively other shapes that change the form factor of the card from that of a substantially planar card may also be selected by one of ordinary skill in the art such as any shape that has at least three substantially straight sides u201c substantially rectangular u201d or other shapes may be considered to be nonplanar when the height to width ratio h w fig6 c is at least approximately 0 5 height or thickness h is the shortest overall dimension in cross section and width w is the longest overall dimension perpendicular to h a shape may be considered to be planar when the height to width ratio is less than approximately 0 5 fig7 shows another embodiment of a sim card 110 the card 110 includes a body 112 a head 114 and six electrical contacts 116 a 116 f as shown in fig8 the body 112 is circular in cross section and the head 114 is rectangular again the shapes may.