A M.wrote a review of Icebreaker Siren LS Sweetheart Top - Women's on November 19, 2018
Familiarity: I've used it several times
Fit: Runs small
I own several merino wool baselayers, but my "go to" is the Icebreaker siren sweetheart. The 150 weight means it layers well and the sweetheart neckline means it layers perfectly under polo shirts and V neck t-shirts. I think the gray and fawn heather shirts are made at a different factory than the black shirts. My new black Icebreaker feels thicker and coarser, still softer than the competitors, but not as soft as my new gray Icebreaker.