New and Used Specialized Command Post IIRC Internal routing, 30.9mm x 125mm, $89. Also have 100mm drop. These are the most durable droppers when not overpressurized.
This is the only dropper that also provides a roughly 1" setback, great for frames that are a bit too short, or just wanting a slacker seat tube angle. It works VERY well for this.
A unique feature is that it has a detent with 1" drop, the perfect position for technical riding. Makes the dropper less of a guessing game.
$69 used
$89 new
I-10 and Chandler Blvd
See my "other items" link for more parts and TIRES