Reference 110.633 is a two-register, automatic chronograph (12 hour capacity) with a deep blue dial and orange hands and accents

Reference 150.633 B is a two-register, automatic chronograph (30 minute capacity) with a deep blue dial and orange hands and accents

Reference 150.633N is a two-register, automatic chronograph (30 minute capacity) with a black dial and orange hands and accents

Reference 740.633 is a two-register, manual-wind chronograph (12 hour capacity) with a deep blue dial and orange hands and accents

The Reference 11633 chronograph is an automatic chronograph, with a fixed bezel for Tachymeter and Pulsations, and a rotating bezel for Minutes and Hours; not called a "Calculator", but uses the same case as the Calculator