Velo Orange's Zero Setback Seatposts have garnered a lot of popularity with MTBs and bike packing riders for their strength and ease of adjustment. 

The seatpost is internally ovalized to reduce weight (295g), and the head is integral with the post, not pressed on as on many modern posts. These factors combined makes for a super strong and light perch.

All forms of adjustment can be done with a single 5mm wrench to the side of the clamping mechanism. Installation instructions can be found here and a short video on assembly can be found here (starts at 31:58) on a build VO did.

27.2mm x 400mm. Maximum height (above the min. insert line) is about 300mm. Available in Polished Silver and Noir.