Following tips in this thread and using Klever Ballistol gun bluing, oil and K2 Wax I've reached some good not perfect results.
Before:
After degreasing and applying 3 coats of blue solutions:
After soaking overnight and applying wax:
Shipping costs will be 15€ , also have this post for sale with 27.2 silver one here:
https://www.retrobike.co.uk/threads/controltech-27-2-sliver-and-27-0-black-seatposts.494651/
For sale two Controltech seatpost: silver 27.2 and black 27.0 uncutted. Both are 350mm full length. Black is slightly curved - can be used as is or cutted to 22mm (by me before shipping if requested). Silver is troublefree, only cosmetic marks.
SOLD. Price is 50€ 47€ 44€ for both.
Please note...