The M35, M40, and M42 are German World War II helmet shell patterns told apart by rim treatment and vent construction, not paint or decals.
A rolled rim says M35 or M40. A raw, flared edge says M42. Then check the vents: separate bushings pressed into the shell mean M35; stamped openings mean M40. Run these two checks in that order and most identification questions are settled before you read a maker code. Decals, liner, chinstrap, and paint can be wartime replacements or postwar additions, which is why collectors who lead with those features misidentify shells constantly.
What Separates The Three Shell Patterns?
Each pattern marks a production step toward cheaper, faster manufacturing, and the changes land in a predictable order: rim first, then vents.
- M35 (M1935). Introduced 1935, built until roughly 1940. Rolled inward rim, smooth to the touch. Vents were separate metal bushings inserted after pressing.
- M40 (M1940). Introduced 1940 as makers moved off M35 tooling. Rolled rim stayed; vent openings were stamped straight into the steel, cutting a parts and fitting step.
- M42 (M1942). Introduced 1942, used to the war’s end in 1945. Rolled rim eliminated entirely, leaving a raw, outward-flared edge. Vents remained stamped.
The visible consequence: the M42 edge catches a fingertip and often shows a sharp lip, while the other two curl under and feel finished. Under bright light the flared edge also throws a different shadow line along the skirt.
M35 vs M40 vs M42: The Shell Comparison
| Model | Rim And Vents | Production Notes |
|---|---|---|
| M35 | Rolled-in rim; separate inserted vent bushings | 1935 introduction, built until about 1940; original prewar and early-war pattern |
| M40 | Rolled-in rim; vents stamped directly into shell | 1940 introduction; simplified build that kept the rolled rim |
| M42 | Raw outward-flared edge; vents stamped directly into shell | 1942 introduction, in service through 1945; rolled rim dropped for speed |
| Size 66 | Rolled or flared depending on pattern | Common pairing is a 59–60 liner band, roughly US 7 3/8 to 7 1/2 |
| Weight | Pressed steel, all patterns | About 1.2–1.4 kg overall, varying with size, liner, paint, and corrosion |
| Maker codes | Stamped into shell | ET, EF, NS, SE, Q, and HKP appear across production; conventions vary |
| Fittings | Liner and chinstrap systems | Broadly similar across all three; fittings can be swapped between shells |
Does Size, Weight, Or A Maker Code Prove The Model?
No. None reliably dates a shell, and treating them as proof starts most misidentifications. Common shell sizes run 60, 62, 64, 66, and 68, with 70 and 72 rare. These are shell and liner-band designations, not US hat sizes — a 62 pairs with liner bands 54 or 55, a 64 with 56 or 57, and a 66 with 58 or 59. Weight sits around 1.2–1.4 kg but shifts with shell size, liner, chinstrap, paint, corrosion, and replacement parts, so a scale reading identifies nothing alone.
Maker codes help but don’t settle it. Stalingrad Front associates the M35 with ET codes, the M40 with ET, and later M42 output from 1943 with CKL/ckl markings. Surviving examples and stamping conventions vary enough that a code alone is thin evidence. If you’re sorting a shell you own or weighing a purchase, this tested roundup of World War 2 German helmet options covers how originality and condition affect value.
Which Identification Mistakes Cost Collectors Money?
Five errors account for most bad calls: labeling every rolled-rim helmet an M35 (the M40 shares that rim; only the vents differ); confusing shell size with liner size; dating by paint color; reading a visible decal as proof of originality (M35 shells may have carried two originally, while later regulations, repainting, camouflage, reissue, and decal removal created countless exceptions, and M40 and M42 examples turn up with one decal, none, or postwar reproductions); and trusting an intact liner and chinstrap as proof the whole helmet is period-correct, when fittings were swapped freely.
Two habits protect you. Don’t sandblast, repaint, polish, or chemically strip a possibly original helmet before an expert sees it — that destroys historical evidence and value in minutes. And don’t wear one: these are collectibles, not protective equipment, and corrosion, drilled shells, weakened steel, altered liners, and unknown restoration rule out ballistic, industrial, or motorcycle use. Prices vary too widely by originality, maker, size, and provenance for one figure to mean anything; a dated auction result beats a dealer asking price every time. The ww2depot collector guide and the IMA listing for an original M40 shell size 66 show how condition and configuration get described in practice.
Common Questions
Can a helmet have M35 vents and an M42 rim?
Not from the factory. Each pattern’s rim and vent treatment moved together in a fixed production sequence, so a shell showing inserted vent bushings alongside a raw flared edge indicates postwar alteration or a reproduction. When the two features disagree, trust the vents as the earlier indicator and look closer at the rim for grinding or reshaping.
Are M35 shells worth more than M42 shells?
Not automatically. Earlier production is scarcer in untouched condition, but value follows originality, maker, size, decals, camouflage, and provenance more than pattern alone. A clean, complete M42 with documented history can outperform a stripped M35 shell. Judge each helmet on its own condition.
Should I clean rust off an original shell?
Leave it until an expert has seen it. Mechanical or chemical cleaning removes the surface evidence collectors use to judge originality and age, and the loss is permanent. Stable red rust on a stored helmet is better managed by controlling humidity than by scrubbing the steel.
Sources
- WW2 Depot. “German Helmets of WW2: M35, M40, M42” Supports the rim-and-vent identification sequence and model dates.
- Stalingrad Front. “German Helmets of World War II” Supports maker-code associations and shell/liner size pairings.
- IMA-USA. “Original German WWII M40 Stahlhelm Steel Helmet Shell, Size 66” Illustrates how condition and configuration are described for a specific shell.