Gruen Precision 510 Rss

Gruen Precision 510RssCA - Cal.N510CA / "Day-Night Hour Jump Dial" / Rotating 12‑Hour Color Change Disc NEW OLD STOCK / Civil Airflight Pilot / Sunburst Dial 1960

Basic Info Listing code : QF7194 Brand : Gruen Model : Precision Reference number : 510 RSS Dealer product code : 06/1/2026 Movement : Manual winding Case material : Steel Year of production : 1960 (Approximation) Condition : Used (Very good) Most Recent Servicing : January 2, 2026 Scope of delivery : No original box, no original papers Gender : Men's watch/Unisex Location : Canada, Mississauga,Ontario Price : C$1,600 Availability : Item is in stock Caliber Movement : Manual winding Caliber/movement : 510 Power reserve : 42 h Number of jewels : 17 Frequency : 18000 Hz Case Case material : Steel Case diameter : 35 x 43 mm Thickness : 10 mm Water resistance : 1 ATM Crystal : Plexiglass Dial : White Dial numerals : No numerals Bracelet/strap Bracelet color : Black Bracelet thickness : 5 mm Lug width : 18 mm Clasp : Buckle Clasp material : Steel Buckle width : 201 mm Functions Jumping hour Other Central seconds, Luminous numerals, Only Original Parts, Vintage ️INTERNATIONAL SHIPPING WORLDWIDE SHIPPING via DHL EXPRESS — DELIVERY in 1–3 business days — FULLY INSURED PACKAGE — SIGNATURE REQUEST Import duties, VAT, and customs charges are always the responsibility of the buyer, according to the laws of the destination country. Important Notice: Temporarily, I am not shipping to the European Union due to ongoing EPR registration requirements. Shipments to all other countries remain available. --- Gruen Precision Day‑Nite Hour Jump Dial – Ref. 510 RSS CA – Cal. N510CA / MINT CONDITION Movement - Caliber: Gruen N510CA - Type: Manual‑wind mechanical - Complication: Day‑Nite Jump Dial with rotating dual‑color disc - Display: Central sweep seconds - Mechanism: 12‑hour automatic color shift (black for day, green radium for night) - Protection: Original movement dust cover Case - Diameter: approx. 35 mm (depending on CA or RSS CA variant), 37 mm including crown - Material: - 510 RSS CA : chromed case - Caseback: Stainless steel, screw‑down - Crown: Original, unsigned (correct for the period) Dial - Finish: Silver sunburst - Architecture: Open windows revealing the Day‑Nite rotating disc - Hour Markers: Dual‑color (black daytime / radium‑green nighttime) - Hands: Original radium‑filled hands Strap - Lug width: 18 mm - Fitted with a vintage‑style leather strap (non‑original) --- Historical Background The Day‑Nite series was introduced in the early 1960s as a civilian evolution of the jump‑disc technology first showcased in the 1958 Gruen Airflight, an instrument originally developed for U.S. Air Force pilots. While the Airflight displayed a dramatic 12‑to‑24‑hour numerical jump, the Day‑Nite model explored a more elegant and artistic interpretation: - a rotating internal disc - two contrasting sets of hour markers - an automatic color change every 12 hours (daytime black → nighttime radium green) This complication is exceptionally rare in the vintage market and represents one of Gruen’s most creative mechanical experiments. The 510 CA / 510 RSS CA references are considered the definitive Day‑Nite variants, distinguished by their open‑window dial architecture and the dedicated N510CA movement.