The little rubber O-ring that goes around the heater pipe which plugs into the lower radiator hose/engine block flange, on 1997-99 models Pt No. KKY0115287 is 20 mm Dia and 3mm in thickness, just in case someone wants to get an alternative to the KIA part. Looks like a plain old o-ring to me......
Note, it is round in shape, if yours leaks like mine and it looks flat, it isn't meant to be flat!! <img src="/forums/images/graemlins/drunk.gif" alt="" /> <img src="/forums/images/graemlins/cheers.gif" alt="" />

KIA, More dirt for ya dollar! 99 Sportage, Pod filter, Bosch Super4 plugs, electric thermo fan, racing pedals, Narva 100W driving lights, Yokhama 235/75R15 Super Diggers....getting to the rest bit by bit.