Short answer

A replica Ballon Bleu "extra large" is a copy of the Cartier Ballon Bleu de Cartier in a 42 mm or 46 mm case. Sellers use "extra large" and "XL" for both sizes. The 42 mm version holds an automatic movement. The 46 mm version holds an automatic movement with a date window. Copies ship with a blue cabochon in the crown, a steel case, and a sapphire or mineral crystal. Cartier does not use the term XL on the dial. That label comes from resellers and listing sites.

Case sizes and weight

The 42 mm case measures 42 mm across, 13 mm thick, and about 52 mm from lug to lug. The 46 mm case measures 46 mm across, 14.5 mm thick, and about 56 mm from lug to lug. A steel 42 mm original weighs near 120 g on the bracelet. The 46 mm sits near 140 g. Most replicas land within 10 g of those figures. Low and mid tier cases use 316L stainless steel. Some top tier sellers advertise 904L steel. Cartier uses 316L on the Ballon Bleu, so 904L is a replica feature, not a match to the original.

Movement

Three movements appear in 42 mm and 46 mm replicas. The Miyota 9015 is a 24 jewel Japanese automatic at 28,800 vph with a 42 hour power reserve. The Seagull ST2130 is a Chinese clone of the ETA 2824-2, 25 jewels, 28,800 vph, 38 hour reserve. The ETA 2824-2 or Sellita SW200 sit in the top tier at a higher price. Quartz versions exist in the 42 mm size. A quartz movement keeps the case 1 mm to 2 mm thinner. Hacking and hand winding work on all three automatic options.

Crown and cabochon

The crown sits under a curved guard at 3 o'clock. The cabochon is a blue stone 2 mm to 3 mm across. Cartier sets a synthetic spinel. Replica cabochons are glass on the lowest tier and synthetic spinel on mid and top tiers. Check the color in daylight. Glass reads flat and dark blue. Spinel reads lighter blue with visible depth.

Dial, hands and crystal

The dial carries a guilloché pattern of concentric rings. Roman numerals sit on a raised inner track. The 42 mm and 46 mm versions both show a date at 3 o'clock. Cartier fits blued steel sword hands. Replicas use blued steel or painted steel. Painted hands look flat at an angle. Crystals are sapphire on mid and top tiers and mineral glass on low tiers. Anti reflective coating on the inside face cuts glare. Some low tier pieces coat the outside face, which scratches.

Bracelet and clasp

The bracelet is a five row steel link design with a hidden folding clasp. Cartier links use screws. Replicas use screws on top tiers and push pins on lower tiers. Screw links make sizing easier and match the original. End links should sit flush against the case with no gap. Clasp width differs by size and version. Ask the seller to measure it in millimeters.

Water resistance and service

Sellers list 30 m to 50 m of water resistance. That rating is not tested on most replica pieces. Gaskets sit at the case back, crown and crystal. Skip swimming and showers. Have a watchmaker pressure test the case before any contact with water. Automatic movements need service every 5 to 7 years. Local watchmakers may decline replica work. Ask before you buy.

Price bands

Low tier 42 mm quartz copies run $60 to $120. Mid tier automatic copies run $150 to $300. Top tier copies with a Miyota 9015 or ETA 2824-2 run $300 to $600. A 46 mm case adds $30 to $80 over the 42 mm price. Cartier 42 mm Ballon Bleu steel models start near $7,000 at retail.

Checks before you buy

  • Ask for the case diameter in millimeters and a photo with calipers.
  • Ask for the movement name and the beat rate. 28,800 vph means a mechanical sweep.
  • Ask for a photo of the crown cabochon in daylight.
  • Ask for the lug to lug measurement. 52 mm fits most 7 inch wrists. 56 mm needs a 7.5 inch wrist or larger.
  • Confirm the bracelet uses screws, not push pins, if you want the original look.