[list=1][*]928s/s4 86-88,944t 86-89,944s2 87-89,944ts 88 these use 36/44 pistons and are the recognizable by their large size and radial mounts. This is a 928S4/993 front ignore the color
[*]944t/s2 89-91,968 92-95 these use 36/40 pistons and are recognizable by their small size and axial mounts. This is the small caliper
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There were some oddballs used at times so it's best to pop the pistons and measure to be sure
One last issue, there are 2 styles of piston/seal
New style
Old style
