Genuine Lead set for the 77 Trans Am ONLY with the Olds 403 in it. All correct length per lead, note that 2 leads that go on the spark plug... have 90 degree end caps on the 77 403 models... but NOT on 1978-79's GM Lead sets..  the latter will also fit ok.. and may be better for those with hedders now fitted too...

You don't buy these often in a ten year vehicle life.. you can change lots of other things but  keeping the ignition / ignition system at its factory best has some merits.....