DIEM. Essentials
The Oak Shirt
The Oak Shirt
Size guide
Size guide
1 - XS/S
2 - M/L
3 - XL/XXL
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The Oak Shirt
A relaxed everyday shirt designed to adapt to the way you live.
Why We Designed It
The Oak Shirt was created to be one of the most versatile pieces in Form 01.
Its relaxed band collar, clean silhouette, and unisex fit allow it to be worn on its own, layered through the seasons, or shared between wardrobes. Designed with everyday life in mind, it's a piece that feels effortless wherever the day takes you.
Size & Fit
Our size guide shows finished garment measurements, not body measurements. For the best fit, compare these measurements with a similar garment you already own.
| 1 — XS/S | 2 — M | 3 — L | |
|---|---|---|---|
| Body Length | 27.2" | 27.6" | 28.0" |
| Shoulder | 17.9" | 18.7" | 19.5" |
| Chest | 40.6" | 42.1" | 43.7" |
| Waist | 40.6" | 42.1" | 43.7" |
| Sleeve Length | 9.3" | 9.4" | 9.6" |
| Sleeve Opening | 13.6" | 14.0" | 14.4" |
Measurements are approximate and may vary slightly between individual garments.
Thoughtful Details
• Relaxed unisex fit for comfortable everyday wear.
• Minimal band collar for a clean, timeless silhouette.
• Button-front design for versatile styling.
• Breathable TENCEL™ and linen blend with a soft, natural drape.
• Designed to be worn on its own or layered with ease.
• Thoughtfully constructed for lasting everyday wear.
Materials & Care
Materials
70% TENCEL™ Lyocell
30% Linen
Chosen for its breathable comfort, soft texture, and natural drape, making it an easy piece to wear throughout the year.
Care
• Machine wash cold
• Gentle cycle
• Wash inside out
• Wash with like colors
Shipping & Returns
Shipping
• Orders typically ship within 1–3 business days.
Returns
• Returns accepted within 30 days of delivery.
• See our Shipping Policy and Refund Policy for full details.
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