Yes, they are, although I can mention one or two even more T-shaped if your sitbone width is narrower. I'm riding a Selle Italia Turbomatic now, which has an effective width around 150mm or so, though I'm one of the few here that that saddle works for. SI makes an even more T-shaped saddle called the SLR Monolink, but they're pretty expensive (carbon rails and shell) and are only 131 mm wide, too narrow for me.