Onsen Stack | No. 341Unisex Long Sleeve T-Shirt

Structural Specifications: Silhouette 3501

We do not compromise on the foundational canvas. Silhouette 3501 is engineered for its exact balance of structural drape and tactile endurance. Designed as an uncompromising, genderless layer, it provides a clean, continuous line that serves as the essential bridge in your daily rotation—substantial enough to hold its shape, yet refined enough to layer seamlessly.

The architecture of this garment is built to dictate form, not restrict it. It features rigorous side-seamed construction, a coverstitched crew collar, and structured 2-inch ribbed cuffs that maintain absolute control over the sleeve break. The interior is rendered strictly tagless, ensuring zero physical friction.

Material Architecture: Solid artifacts are forged from 100% Airlume combed, ring-spun cotton. Heather variants utilize a deliberate 52/48 cotton-poly blend to achieve a specific visual frequency (Athletic and Black Heathers utilize a 90/10 ratio). Operating at a precise 4.2 oz./yd.² (142.4 g/m²) with a 32-single thread count, the fabric delivers a dense, premium finish.

Assembled across our global fabrication network (US and the Americas) under strict ethical and environmental protocols, ensuring every artifact meets the ichinichi standard before it is commissioned for your wardrobe.

Every ichinichi piece is made on demand, only after it is ordered. This keeps us out of the cycle of excess inventory and unnecessary waste.

Your garment is produced specifically for you, with a typical 3–4 day fabrication period before shipping. It is a slower, more deliberate model, but one that lets us make only what is needed and keep the process focused on quality rather than volume.

Nothing is pulled from a stockpile. Your piece is made for your daily rotation when you commission it.

ichinichi ships worldwide, with complimentary shipping on every order.

To reduce unnecessary transit and support our on-demand model, we work with a decentralized production network across the US, EU, UK, and Japan. Whenever possible, your piece is produced at the facility closest to your destination.

After a typical 2–5 day fabrication period, most orders arrive within 3–6 days, depending on region. Delivery times may vary internationally, but each order is routed through the nearest available production hub.