Brand: REI Co-op.

Style: Mens lightweight lined athletic sweat shorts with elastic waistband and casual running silhouette.

Size: Mens Medium (M per interior printed size marking).

Color: Golden yellow shell with subtle tonal grid pattern and gray interior lining.

Materials: Main body 73% nylon and 27% spandex; external waistband 71% nylon and 29% spandex; liner 86% polyester and 14% spandex (per interior label).

Fabric type: Lightweight microfiber woven shell with stretchy, quick-drying performance and a smooth breathable knit liner.

Design details: Wide elastic knit waistband with rear bungee-style drawcord, split side hems for mobility, and built-in stretch liner short for coverage and support.

Pattern and graphics: Allover small check grid pattern on the shell with reflective REI Co-op logo printed at the left leg and a small reflective tab at the back hem.

Features: Elastic waistband with adjustable drawcord, breathable lined interior, slash hand pockets, rear zip pocket at the waistband for secure storage, lightweight packable construction, and soft smooth seams for comfort during movement.

Theme and occasion: Versatile outdoor and athletic shorts ideal for running, hiking, gym workouts, travel, and casual everyday wear.

Season and use: Best suited for spring and summer activities or year-round indoor training.

Country of origin: Made in Vietnam (per interior label).

Care instructions: Machine wash cold, do not bleach, tumble dry low, do not iron, and do not dry clean (per printed care information).

Style codes and identifiers: Interior print shows REI Co-op branding, size Medium, fabrication percentages, and care instructions; a specific style number or UPC is not visible in the photos.

Special notes: REI Co-op mens Medium yellow lined athletic shorts with grid-check shell and reflective logo details; review all listing photos for additional views of the waistband, liner, pockets, and overall design.