BY Men Nightwave — Black Abstract Print Short-Sleeve Rash Guard

BY Men Shipping
Tracked shipping available to supported destinations. USA & Canada: estimated 8–10 business days; international: estimated 12–20 business days. Shipping is calculated at checkout. BY Men items ship separately from our regular collection and do not qualify for standard free-shipping offers. Delivery estimates can vary.

Bold in the water. Effortless beyond it. The BY Men Nightwave Black Abstract Print Short-Sleeve Rash Guard brings a fresh edge to coastal dressing. Fluid, multicoloured abstract linework moves across a dark base, creating a distinctive look for swimming, beach days and active afternoons. A fitted, stretch-friendly silhouette makes this piece as practical as it is eye-catching.

🌊 The Nightwave Statement

• All-over black design with playful, multicoloured abstract curves and linework.
• Short sleeves and a streamlined silhouette for a modern, athletic look.
• A standout layer for swim sessions, surf days and laid-back coastal style.

✨ Stylish Yet Practical

• Moisture-wicking fabric that feels soft, flexible and comfortable in motion.
• UPF 50+ sun protection for covered areas of skin.
• Flatlock seams for a smooth, sporty finish.
• Fitted cut that layers neatly with swim shorts and casual bottoms.

🖤 Why You'll Love It

• Original BY Men attitude with a bold but wearable graphic print.
• Stretch fabric designed for movement in and out of the water.
• Available in XS–2XL; use the body measurement charts below to choose your size.
• Easy to pack for holidays, waterside workouts and weekend getaways.

✨ Complete the Look

Pair Nightwave with black swim trunks for a sharp beach-ready look, or wear it with relaxed shorts after your swim. Discover BY Men Swimwear, browse BY Men New Arrivals and explore the full BY Men collection.

🧵 Fabric & Fit

• US fulfilment fabric: 78% polyester, 22% elastane; approx. 8.56 oz/yd² (290 g/m²).
• EU fulfilment fabric: 88% recycled polyester, 12% elastane; approx. 6.78 oz/yd² (230 g/m²).
• Fitted cut with soft, stretchy, moisture-wicking fabric.
• UPF 50+ protection; recycled content certified to the Global Recycled Standard (GRS), with OEKO-TEX Standard 100 certification as supplied.
• Printed design positioning and colours may vary slightly by garment and screen.

🧺 BY Men Quality & Care

To help maintain the colour and fit, rinse after swimming, machine wash cold on a gentle cycle with similar colours, and air dry when possible. Avoid bleach and fabric softener. Do not iron directly over the print or expose the fabric to high heat.

📏 Find Your Fit — Size Guide & How to Measure

These are body measurements, not flat garment measurements. Measure around the fullest part of your chest, your natural waist and the widest part of your hips. The rash guard is designed for a fitted feel; review the measurements before choosing a size.

Body measurement chart — inches

Body measurement chart — centimetres

Measurements are intended as a sizing guide. Minor production variations may occur.