The Rolex Explorer II Reference 16570 "Polar" A-Series with a "Swiss Only" dial is a highly coveted "neo-vintage" configuration among watch enthusiasts and collectors. This specific iteration represents a very narrow, transitional window in Rolex production history.

• Reference 16570 ("Polar"): The defining 5-digit generation of the 40mm Explorer II produced from 1989 to 2011. The "Polar" variant features a distinct white dial with high-contrast, black-outlined hands and hour markers. 

• "A" Serial Number: The letter "A" at the beginning of the serial number dates the production of the case specifically to 1999. 

• "Swiss Only" Dial: This is the ultimate collector detail for this era. Printed simply as "SWISS" at the very bottom of the dial (6 o'clock position), it marks Rolex's brief 18-to-24-month transition (roughly late 1998 to early 2000) from radioactive Tritium lume to non-radioactive LumiNova. By late 1999/2000, dials were updated again to read "Swiss Made" when Super-LumiNova took over. 

• Full Set: This specifies that the watch is accompanied by all its original factory packaging, including the outer box, inner green box, instruction booklet, paper warranty certificate (bearing the matching "A" serial), and extra bracelet links.

• Feature	Specification
  Case Diameter	40mm (approx. 12.2mm thickness)
  Case Material	Stainless steel with drilled lug holes (typical for 1999)
  Bezel	Fixed, brushed stainless steel with 24-hour markers
  Μηχανισμός	Rolex Caliber 3185 Automatic GMT movement
  Λειτουργίες	Hacking seconds, quickset independent local hour hand, date window
  Luminescence	Green LumiNova (signed "SWISS")
  ΜΠΡΑΣΕΛΕ	Oyster bracelet (Reference 78790) with hollow end-links and micro-adjust clasp
  Water Resistance	100 meters (330 feet) via Twinlock screw-down crown