Saab 9-3 muffler and tip, heavy duty clutch and pressure plate, stiffened and lowered springs, firmer dampers, as well as stronger CV joints and driveshafts. In 1999, the Viggen was the first 9-3 to use Saab's Trionic 7 engine management system. The 2001 model year introduced a Traction Control System (TCS). The TCS was later made available in the SE line. The car featured a rear wing that required relocating the radio antenna, aerodynamically designed bumpers and side skirts, special bolstered and colored leather seats (in four colors: black with black inserts (charcoal), black with blue inserts (deep blue), black with orange
Order-7-3 triangular honeycomb 2-hypercycle, each of which has a limiting circle on the ideal sphere. The Schläfli symbol of the "order-7-3 hexagonal honeycomb" is {6,7,3}, with three order-5 hexagonal tilings meeting at each edge. The vertex figure of this honeycomb is a heptagonal tiling, {7,3}. In the geometry of hyperbolic 3-space, the order-7-3 apeirogonal honeycomb (or ∞,7,3 honeycomb) a regular space-filling tessellation (or honeycomb). Each infinite cell consists of an order-7 apeirogonal tiling whose vertices lie on a 2-hypercycle, each of which has a limiting circle on the ideal sphere. The Schläfli symbol of the apeirogonal tiling honeycomb is {∞,7,3}, with three "order-7