Launched in the early 1970’s, the Heuer Calculator chronograph Ref.110.663 measures 45.5mm across the lugless stainless steel case. Featuring the self-winding Heuer calibre 12 this watch features a 2-part slide rule for conducting mathematical calculations on the fly. I remember when the Calculator changed hands for about £300 in the 1980’s; the width and height of the case felt massive at the time and although still a big watch it still has a presence on the wrist that with the orange and blue colourway is eye catching from across the room. The vintage Heuer collector market experienced a peak in the late 2010s but the Calculator unlike the McQueen “Monaco’ or the Jochen Rindt ‘Autavia’ never reached the inflated prices of those “iconic” models. It’s no surprise that there has been little mention of TagHeuer re-issuing the unloved Calculator. More’s the pity as the 45mm width is the same as the contemporary Tag Heuer Connected SBG8A12.BT6219 and probably wouldn’t look out of place in the current line up.