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Rolex · Explorer II

Explorer II

Ref. 16550

discontinuedSapphire transitionDocumentedLast reviewed Not yet reviewed

Authentication Notes

Crystal

Medium

Sapphire, not acrylic

The 16550 introduced the sapphire crystal; an acrylic crystal indicates a 1655 (or a wrong service part).

Dial

HighProbable

Rail / cream Polar dials

Early white dials show a distinctive text spacing ('rail dial') and frequently aged to cream; both traits are heavily faked. Verify against known-correct 1985–1989 examples.

Movement

HighHigh confidence

Caliber 3085 only

The 16550 uses the 3085 exclusively (first independent 24h hand). A 3185/3186 belongs to the later 16570.

Inspection points

No inspection checklist has been published for this reference.

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