Top pick: the hand-wound tier with a decorated three-quarter plate and an engraved balance cock, because the back of the watch has to support the front. Four criteria decide the rest: movement decoration, case and lug geometry, dial and outsize date execution, and the paperwork a seller shows you before payment. The sections below take each criterion in turn, then sort the market into three tiers with a use case for each.

Reference 405.031 and the "Lange 2" Label

A. Lange & Söhne numbers its watches with a model code plus a metal and dial code, so 405.031 points to one case and dial combination rather than a whole family. Search strings and listing titles often say "Lange 2," a name that does not appear in the brand's catalog. Treat the listing text and the reference number as two separate claims and confirm both against the brand's own reference page before you compare replicas. If a seller cannot say which model family the number belongs to, the listing is guesswork.

Criterion 1: Movement Decoration

Lange finishing is the hardest thing to fake at a low price: Glashütte ribbing on a three-quarter plate, blued screws, gold chatons, and a balance cock finished by hand. A replica either shows those elements under a display back or hides them behind steel.

  • Pros of a decorated movement: the watch reads correctly from both sides, and the engraved balance cock is the detail collectors check first.
  • Cons: plating can flake, engraving is usually machine-cut, and service options are thin.
  • Pros of a plain movement: lower cost, fewer parts to fail, nothing pretending to be hand work.
  • Cons: a solid caseback on a Lange-shaped watch is a visible mismatch for anyone who has handled the original.

Best for: buyers who wear the watch face up and never show the back can take the plain movement. Everyone else should pay for decoration.

Criterion 2: Case, Lugs, and Crystal

Lange cases are thick enough to hold a movement with a large date mechanism, and the lugs curve toward the wrist instead of standing straight. Replica cases fail in two places: lugs that are too thin, and a sapphire crystal that sits flat instead of domed. Check the profile from the side, then check the crown, which should sit flush at 3 o'clock with no gap at the tube.

  • Pros of a machined steel case with a proper lug curve: sits close to the wrist, holds the original proportions, takes a strap without twisting.
  • Cons: polished surfaces scratch, and cheap cases lose their edge lines after a polish.
  • Pros of titanium or coated cases: lighter on the wrist, less glare.
  • Cons: color and sheen rarely match the gold or platinum the reference was built in.

Best for: daily wear, where case weight and lug fit matter more than any single dial detail.

Criterion 3: Dial, Printing, and the Outsize Date

Dial work is where most replicas give themselves away. Look at three things: the printed text under 12, the sharpness of the applied markers, and the outsize date. On a real Lange the date discs are separate and the two numerals sit on one baseline. On a weak replica the date window is a single printed disc, the numerals tilt, and the font runs heavier than the original.

  • Pros of a two-disc date: correct look, correct shadow behind the numerals.
  • Cons: more moving parts, more to break, and a jump that can stick.
  • Pros of printed markers: cheaper and flat.
  • Cons: no depth, and light catches them the wrong way.

Best for: buyers who judge the watch at arm's length in daylight. For that group this criterion outranks the movement.

Criterion 4: Strap, Buckle, and Papers

Strap quality and buckle engraving are the cheapest places to cut and the easiest things to inspect. Ask for photos of the buckle tang, the stitching line, and the inner lining. Then ask what arrives with the watch: box, card, and a written description of the movement. A seller who sends clear movement photos before shipping is a seller worth dealing with.

The Three Tiers on the Market

Tier 1: Quartz or Basic Automatic, Solid Back

  • Pros: lowest price, light, accurate if quartz, nothing to service.
  • Cons: wrong caseback, wrong thickness, no movement worth showing.

Best for: a one-off costume need where nobody handles the watch.

Tier 2: Decorated Automatic Clone

  • Pros: display back with ribbing and blued screws, automatic winding, mid-range price.
  • Cons: rotor blur hides the plate, engraving looks stamped, winding feel is coarse.

Best for: buyers who want a display back and will not compare it side by side with a genuine piece.

Tier 3: Hand-Wound, Decorated, Display Back

  • Pros: closest match to Saxon finishing, correct plate shape, engraved balance cock, correct hand-wind ritual.
  • Cons: highest price, needs winding, harder to service, availability varies.

Best for: collectors who own or handle real Lange watches and want the visual language right.

Checks Before You Pay

  1. Confirm which Lange family the 405.031 number belongs to.
  2. Request a side profile photo for lug curve and case thickness.
  3. Request a movement photo with the caseback open, in focus, under bright light.
  4. Zoom the date window: two discs, one baseline, correct font weight.
  5. Ask about the crystal dome and whether it distorts at the edges.
  6. Agree on a return window in writing before payment.

Use-Case Recommendation

If the watch stays under a cuff, buy Tier 1 and save the money. If it comes out at dinners and the back gets shown, buy Tier 2 and accept the rotor. If you own genuine Lange pieces or handle them often, buy Tier 3, because the plate, the chatons, and the balance cock are the whole point of the reference. Anywhere else you are paying for a dial that a trained eye reads in two seconds.