Vital S3 Zip-Off Bottom | Black

Best For:Mid-Weight Fleece Base Layer

Boosted by XLANCE®, the all-new Vital S3 is our most advanced fleece base layer to date. Drawing inspiration from the legendary Peloton 97, the Vital S3 delivers upgraded advantages with an improved fit and a more advanced fabric.The full-length leg zippers and above the boot design allow you to easily add or shed layers in changing weather conditions without removing your boots and outer layer pant.

Its ultra-soft brushed fleece interior provides a comfortable next-to-skin feel with exceptional moisture-wicking and quick-drying performance. It keeps you dry and comfortable whether you’re locked in glassing for hours or pushing hard to the next ridge — especially in cold to frigid conditions where a standard base layer falls short.

XLANCE brings entirely new performance to hunting apparel: an advanced polyolefin-based stretch yarn with built-in resistance to sweat, chemicals, heat, ozone, and UVA/UVB radiation. This delivers long-lasting elasticity and garment durability while staying incredibly light. It overcomes the typical pitfalls of spandex and elastane—excess weight, bacterial odor retention, slow drying, and loss of shape over time.

Unlike the aggressive snap-back of traditional elastane, XLANCE provides gentle, low-force stretch that's noticeably more comfortable and fatigue-free during dynamic movement, yet it maintains excellent recovery for season-after-season reliability.

• 28-inch inseam
• Full-length side zippers for easy off and on
• Turbodry® waistband
• Functional fly
• Gusseted crotch for unrestricted mobility
• Flatlock seams for non-chafing comfort
• Soft-brushed fleece interior
• Moisture wicking
• Quick drying
• 4-way stretch
• Odor resistant

• 90% Polyester / 10% XLANCE® – 127 g/m²
• XLANCE – UV- and sweat-resistant stretch fiber for superior durability and shape retention
• Toray Makspec® – Antimicrobial odor resistance

This base-layer bottom is sized with an athletic next-to-skin fit to layer over a brief and under a hunting pant. Only upsize if you measure between sizes.

Layering Example – Cold Conditions:

*For an individual measuring size: L / 36R

Brief: ULTRA Merino Boxer Brief – L
Base Layer: Vital S3 Zip-Off Bottom – L
Hunting Pant: Attack Pant – 36R
Outer-Layer- Waterproof Rain Gear: Yukon TR Rain Pant – L

Additional Resources:

Fit & Layering Guide

KUIU Layering System