The "AN-J-4" Heritage Sheepskin | The Pinnacle of Flight Luxury | Full Grain Apparel

The Rare Breed: A Short-Lived Legend, A Lifetime Statement

Step into the most refined evolution of WWII aviation gear with the "AN-J-4" Sheepskin Jacket from Full Grain Apparel. Introduced in 1943 to replace the bulky B-3, the AN-J-4 was designed to provide the same extreme-cold protection but with a more streamlined, articulated fit for pilots in cramped cockpits. It is the "thinking man’s" aviator—blending the sheer warmth of thick shearling with the structural sophistication of a field jacket. This is a garment for those who appreciate the technical nuances of military history and the uncompromising luxury of natural materials.

"Altitude-Spec" Double-Face Sheepskin & Horsehide Trim

At Full Grain Apparel, we’ve painstakingly recreated the complex construction that made the original AN-J-4 a masterpiece of utility:

• High-Loft "Arctic" Sheepskin: This is a true "Double-Face" hide. The interior is a 15mm-thick wall of natural cream-colored wool, while the exterior is a rugged, weather-resistant leather—all one piece for maximum heat retention.

• Reinforced "Impact" Overlays: true to the original specs, we’ve reinforced high-stress areas (the sleeves, shoulders, and pockets) with top-grain cowhide or horsehide overlays. This dual-leather construction prevents the sheepskin from stretching and adds a striking, multi-tonal aesthetic.

• Hand-Waxed "Seal Brown" Finish: The leather surface is treated with a vintage wax finish that will develop "speed lines" and a unique character as it flexes and ages with you.

The "AN-J-4" Signature Structural Details

The AN-J-4 is distinguished from other bombers by its superior tailoring and adjustable fit:

• Shearling-Lined "High-Rise" Collar: Features a double-strap throat latch. When flipped up, the dense wool creates a soft, impenetrable barrier against freezing winds.

• "Action-Back" Shoulder Gussets: Unlike the boxy B-3, the AN-J-4 features integrated expansion panels. This allows for total arm mobility, making it the most comfortable heavy sheepskin jacket for driving or active wear.

• Internal Storm Cuffs: Hidden within the leather sleeves are recessed, wool-blend knit cuffs that act as a gasket to keep cold air from traveling up your arms.

• Adjustable Side-Waist Buckles: Heavy-duty brass buckles on the hips allow you to taper the fit, ensuring the jacket stays snug against your frame and traps every bit of body heat.

• Period-Correct "Navigator" Pockets: Large, button-flap waist pockets reinforced with leather overlays, offering deep storage and a rugged, military-grade appearance.