Tuck N' Roll Brat Seat Vintage Black. The base plate is from ABS and the foam is sturdy and nice to sit on.
The seats are made of PU (skai) leather due to the fact this will better handle rain and sun. The quality is superb and it does complete every Cafe Racer.
The base plate + foam are like on a modern bike (see pictures) and make the seats strong and light weight. No rust here!