The National Anthem drums were not actually recorded during the Kid A sessions. The drum and bass tracks were recorded in 1997 when Radiohead was working on OKC B-sides, but they decided to save the track for their next album. I don't know if that means Phil was likely using a different kit at that point.

I totally forgot about that o.O I’ll update the previous answer to match.

Phil’s main kit for OK Computer was the Premier Rosewood/Cherry-red XPK Laquer Drum Kit. However, he was using at least some Zildjian K Cymbals during OK Computer era, based on live footage.

Phil performing Airbag on Live… with Jools Holland in 1997.