Brand: Gruen

Model: Precision Day-Nite "Jump" Dial 510 RssCA (Rare Stainless Steel Model); Swiss Made circa 1970s

Case: Solid stainless steel "cushion" case with screw-down back is approximately 36mm excluding the original winding crown

Bracelet: Original Gruen 20mm solid stainless steel "coffin" linked bracelet with Gruen signed fold-over clasp; includes three (3) additional loose links

Movement: Gruen cal. N510CA manual-winding movement (17 jewels) modified for day-night "jumping" function; Swiss Made

Features: Stunning original day and night two-tone "jump" dial with white minute markings; day-night feature where hour markers flip from black during daytime hours (6 AM - 6 PM) to fluorescent nite-glo green during nighttime hours (6 PM - 6 AM); original handset with center sweeping-seconds hand; solid stainless steel "cushion" case with original Gruen "coffin" bracelet

Condition: Fantastic original condition overall with only minor honest wear consistent with age and use; sharp solid stainless steel case appears to be unpolished with a few minor scratches; crisp caseback with all printing clearly visible; attractive original two-tone "Day & Nite" dial; original handset with all luminous material in tact; a few superficial scratches on the domed acrylic crystal

Other: Looking for a unique conversation piece? Look no further than this incredible Gruen Precision Day-Nite! In general, all Day-Nite models are rare in any condition and we see very few in solid stainless steel. This particular example is in superb condition and even comes mounted on its original stainless steel Gruen linked bracelet.