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REI Co-op · Budget synthetic thermal half-zip · Budget

REI Co-op Midweight Half-Zip Base Layer Top

Best budgetCold-weather running guide

The value pick: a soft, fast-drying synthetic half-zip that OutdoorGearLab rates a Best Buy, giving up some warmth compared with wool in exchange for a much lower price.

List price
$69.95Men's list price on rei.com. OutdoorGearLab's women's Best Buy is a different item (REI Co-op Midweight Base Layer Crew, $65 in that review), not verified here.
Fits
Men's
Warmth
Midweight
Wind
None
Water
None
Visibility
None
Temperature range
25 to 45°F (−4 to 7°C) Our estimate from the construction
Best for
Runners on a budget who want one warm, quick-drying half-zip for roughly 25-45°F runs or for layering under a shell.
Not for
Runners who want merino's odor resistance for repeat wears or running-specific extras like reflective trim.

Downsides

  • Less warm than wool for its weight, per OutdoorGearLab
  • Reviewer found it harder to layer than some rivals
  • No odor-control or reflective details listed

Specs

Materials92% recycled polyester, 8% spandex; peached face fabric
Fabric weight220 g/m²
FitSemifitted
NeckHalf-zip, high neck
ThumbholesYes
Odor controlNone stated
Style numberC08396

Features

  • 220 g/m² midweight stretch synthetic
  • Peached fabric for a soft next-to-skin feel
  • Half-zip front with high neck coverage
  • Thumbholes
  • Semifitted cut

What reviewers say

  1. Gave the men's REI Co-op Midweight Half-Zip a Best Buy award (listed at $70, 220 g/m²), crediting quick drying, soft stretchy fabric, thumb loops and flatlock seams; marked it down for being less warm than wool and harder to layer.

    OutdoorGearLab: Best Base Layer (GearLab men's guide) · Apr 1, 2026

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