There were 2 series of .18 chips put out for Slot-A. The first was the K75, which was simply a normal Slot-A Athlon with a .18 core and the 512KB of off-die L2 cache. There were also some Tbirds produced in the Slot-A form factor, but I believe those weren't stable past 800mhz or so on a KX133 chipset.