IHM-37-BLK - Oiled Whipcord N1 Deck Jacket - Black

This oiled whipcord N1 is the heaviest and most weather-resistant iteration of Iron Heart’s deck jacket to date. Built from Japanese whipcord that normally weighs 12oz, this version receives a double oil treatment that increases the fabric weight to approximately 14oz while significantly improving water resistance. Whipcord’s dense, tightly woven structure resists absorption, allowing the oil to sit on the surface and form a durable protective layer without softening the fabric or compromising structure.

For this season, Iron Heart updated the oiling process to remove fluorine compounds in favor of a fluorine-free, double-layer oil coating. The result achieves the same level of water repellency as previous versions with a slightly waxier hand feel and added heft. Beneath the shell, the jacket stays true to the original 1940s US Navy N1 specification, featuring a high-density wool and alpaca pile lining, a hidden chino interlining for enhanced wind resistance, and insulated satin-lined sleeves for easier layering. Designed by Shinichi Haraki and handmade by WORKS INC. in Japan, this is a faithful military reproduction refined through modern materials and construction.

• Double-oiled Japanese whipcord, approximately 14oz after oiling
• 100 percent cotton
• Hard-twisted yarn construction
• Twill weave
• Reactive-dyed warp and weft
• Fade-resistant finish
• High-density 80 percent wool, 20 percent alpaca pile lining
• Hidden chino interlining for increased wind resistance
• Quilted satin sleeve lining with lightweight polyester insulation
• Hidden knitted storm cuffs
• Two-way YKK zipper with button-fastening storm placket
• Wool-lined handwarmer pockets with snap fastenings
• Internal snap-fastened utility pocket
• Button-fastened waist cinches and throat latch
• Poly and cotton stitching
• Single and double needle construction
• Internal felled seams
• Dry clean only using petroleum solvent
• Outer shell can be spot cleaned with warm water
• Do not machine wash or tumble dry
• Do not iron or steam
• Natural creasing and wrinkling will develop with wear and is expected
• Made in Japan

Tag Size	Shoulder	Length	Chest (P2P)	Waist	Opening	Sleeve Length	Sleeve Opening
XS	15.8	25.8	21.2	20.4	20.3	25.5	5.3
S	16.5	26.3	21.8	21.1	21.3	25.8	5.3
M	17.5	27.1	22.4	21.8	21.9	26.4	5.5
L	18.2	27.9	23.5	22.4	22.8	26.9	5.6
XL	19.0	28.7	24.1	23.2	23.5	27.5	5.9
XXL	19.6	29.6	24.9	24.0	24.3	28.2	6.1
XXXL	20.5	29.7	25.5	24.8	25.0	28.7	6.1
XXXXL	21.5	30.3	26.3	25.5	25.8	29.2	6.3

A variance of +/-.5" is within tolerance. 

Fit Notes: Shop owner Tommy is wearing a size Large in the pictures. He has been wearing a large in this jacket for several years now which seems to be the perfect size. This is one of those rare Iron Heart pieces that you can buy your true size in, but we would ultimately still recommend sizing up once. Tommy is 5'9," 165lbs with a 40" chest.