Please help identfy these parts?

[toys19]

Hi people have asked me what these parts are on my bike, and I am thinking of splitting so if anyone knows what these parts are and what they might be worth I would be very grateful.
headset? saddle?

[NORTY40]

Seat is similar to my Jaguar aero , under mine it is stamped ' Arzake Aero Jaguar' which looks as though it ties in with what is embossed on the back of yours    Mine also has the 'BMX aero' on the front bit but it looks like it has more holes in it  . As for value I ain't got a clue  

[monkian]

I saw a minty blue one (albeit with different logo on side) go recently on eBay for around £60.
Another nice black one with the BMX AERO text went for around £35.
Hope that helps