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The Stone That Holds It All Together.
Every craftsman knows — the keystone holds everything together. The Keystone Cap honors that principle with refined simplicity and quiet strength.
Featuring a gold-embroidered Masonic emblem on rich cotton, this cap is a modern salute to the brotherhood — where legacy meets street precision. Designed for men who understand that symbols carry stories, this piece completes any look with effortless authority.
- Gold-embroidered Masonic emblem — bold yet refined
- Low-profile, structured men's fit — lodge nights to everyday wear
- Available in 6 colorways: Black, Navy, Cranberry, Spruce, Green Camo, Khaki
- Lightweight 3.3 oz | Adjustable strap | One size fits most
Because in the O3 world, heritage is always in fashion.
The Keystone Cap
$24.99 USD
Size Guide
How to Measure
Chest: Measure around the fullest part of your chest, keeping the measuring tape level under your arms and across your back.
Waist: Measure around your natural waistline without pulling the measuring tape too tightly.
Hips: Stand with your feet together and measure around the fullest part of your hips and seat.
Fit Guidance
For a standard fit, select the size that matches your body measurements.
For a relaxed or oversized fit, consider ordering one size larger.
If your measurements fall between two sizes, choose the larger size.
Product fit may vary slightly depending on the garment style, material and manufacturer.
| Size | Chest (in) | Waist (in) | Hip (in) |
|---|---|---|---|
| S | 34-36 in | 28-30 in | 35–37 in |
| M | 38-40 in | 32-34 in | 39-41 in |
| L | 42–44 in | 36–38 in | 43–45 in |
| XL | 46–48 in | 40–42 in | 47–49 in |
| 2XL | 50–52 in | 44–46 in | 51–53 in |
| 3XL | 54–56 in | 48–50 in | 55–57 in |
| 4XL | 58–60 in | 52–54 in | 59–61 in |
| 5XL | 62–64 in | 56–58 in | 63–65 in |