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  • Armband Running Case Phone Holder-Sporteer Entropy E8
  • iPhone 16 Pro Running Armband Case
  • Sporteer Entropy E8 Modular running Armband is the most comfortable armband for exercising
  • Sporteer Entropy E8 Modular Sport Armband Case for Large Smartphones & Cases
  • Sporteer Entropy E8 Modular Armband for Samsung Galaxy phones with cord strap
  • Sporteer Armband case for iPhone with opening for earbud cord
  • Sporteer Entropy E8 Modular Reflective Armband for safe running at night
  • Sporteer Entropy reflective armband straps for safe night running

Entropy E8 Armband | Fits Large Phones & Rugged Cases

$31.99
$31.99 $34.99
You save 8% ($3.00)
Shipping calculated at checkout.
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Strap Size Bundle

The Ultimate High-Touch Performance Armband

The Sporteer Entropy E8 is engineered for the athlete who needs their tech within reach. While belts are great for storage, the E8 is built for interaction. Designed and tested in Scottsdale, AZ, this armband puts your training data and music exactly where you need it, featuring a unique dual-strap system for a custom fit on bare skin or over gym layers.

Key Performance Features:

  • Direct Access Interface: A premium, touch-transparent window ensures zero-lag interaction with your GPS, heart rate data, and playlists.

  • No-Strip Engineering: Deep-pocket design fits Rugged, Otterbox, and MagSafe cases. Keep your protection on while you hit the pavement.

  • Dual-Strap Versatility: Includes two interchangeable straps. One for summer training on bare arms; one for winter miles over jackets.

  • Memory Foam Comfort: Unlike stiff plastic armbands, our memory foam backing contours to your bicep to prevent pinching and slipping during high-intensity movement.

  • High-Visibility Safety: Integrated reflective trim and strap tabs keep you seen during low-light desert runs or early morning sessions.

Will It Fit My Phone? | 30-Second Fit Check

At Sporteer, we don't believe you should have to guess. The most accurate way to ensure a perfect fit is to measure your setup.

Step 1: Keep Your Case On

Measure your phone while it is inside your protective case (Otterbox, Lifeproof, or Battery case).

Step 2: Check the Dimensions

The Entropy E8 internal pocket comfortably accommodates combinations up to:

  • Length: 165 mm (6.5 inches)

  • Width: 90 mm (3.5 inches)

  • Depth: 16 mm (0.6 inches)

Pro Tip: If your setup fits within these dimensions, it is a guaranteed fit for most "Max" and "Plus" models. (Note: For the larger "Ultra" models, we recommend the Kinetic K1 Belt).

Step 3: Choose Your Strap Bundle

The E8 includes two straps in every box. Choose your bundle based on your arm circumference:

  • S/M Bundle: Small + Medium straps. Fits 8" – 14" (20cm - 36cm)

  • M/L Bundle: Medium + Large straps. Fits 10" – 18" (25cm - 46cm)

Please contact Sporteer Customer Service if you have questions about compatibility with your phone or case.