IWC REF. 378401 BIG INGENIEUR CHRONOGRAPH STEEL
International Watch Co., Schaffhausen, "Big Ingenieur Chronograph",
No. 3009840, case No. 3391027, Ref. IW378401. Made circa 2008.
Very fine, large, tonneau-shaped, self-winding, water-resistant,
stainless steel wristwatch with square button chronograph,
registers, tachymeter, date and a stainless steel IWC buckle.
Accompanied by an IWC original fitted box and international
warranty card.
Three-body, tonneau-shaped, tachometer bezel, polished and
brushed, transparent screwed-down case back and crown, sapphire
crystals.
Bicolor white and black with applied steel luminous baton
indexes, outer minute and seconds divisions with Arabic five-minute
numerals, subsidiary seconds and combined 60-minute and
12-hour register dial, date aperture at 6. Stainless steel luminous
baton hands.
Cal. 89360, rhodium-plated, 40 jewels, straight-line lever
escapement, monometallic balance, shock absorber, self-compensating
flat balance spring, double-pawl automatic winding system,
hack mechanism.