The CTB joins Arnold & Son's Instrument Collection - and, like every other model from Arnold & Son, features an in-house mechanical movement. This line is inspired by the timepieces produced during the second part of John Arnold's life when he and his son, John Roger, dedicated themselves to the quest for absolute precision (thereby establishing themselves as official suppliers to the Royal Navy). 

Underscoring its continued commitment to forward-thinking precision, Arnold & Son's watchmaking experts masterfully rose to challenge of creating a World's First in a wristwatch: a chronograph with a central true beat seconds hand. The magnificent CTB represents the brand's second chronograph and blends the iconic Instrument Collection complication of a true beat seconds, while at the same time remaining true to the line's optic code of superb legibility. This aesthetic direction has been achieved by incorporating a central true beat seconds hand and a central chronograph seconds hand - both on the same axis but with different jumping intervals. A huge technical challenge to have both functions operating from the centre, Arnold & Son's unique invention is protected by two patents. 

Sometimes referred to as a dead beat seconds, the true beat seconds is a precision function wherein the seconds beat incrementally as opposed to sweeping along the dial - allowing for more accurate reading. To accomplish this function in and of itself is no easy feat. However, Arnold & Son has taken the idea to new heights by incorporating the true beat seconds on the same axis as the chronograph seconds hand. The result, when the continually running chronograph hand is started, is visually amazing. It gives the impression that it can catch up to the true beat seconds hand, but this never happens since the true beat seconds hand jumps away each second  in a delightful and entrancing game of cat and mouse.

The A&S7103 calibre is a proprietary mechanical self-winding movement with column-wheel operated chronograph. The movement is configured to give optimum balance and beauty to the dial, with off-centered hour and minutes at 12 o'clock, big central true beat seconds and central chronographs seconds, and 60-minutes chronograph indicator at 6 o'clock. The 31-jewel movement beats at 28,800 vibrations per hour and offers more than 50 hours of power reserve. This world's-first timepiece also offers the efficiency of bi-directional winding thanks to ceramic ball bearings.

Each movement is NAC grey treated and meticulously completed inHaute Horlogeriefinishing with hand-chamfered bridges with polished edges, fine circular graining andCôtes de Genève rayonnantes, brushed and skeletonised rotor, and screws with bevelled and mirror-polished heads. The 44 mm stainless steel timepiece is offered with a light-grey and silvery opaline dial. The dial has a complex multi-level structure with at least three different finishes that offer breathtaking depth and dimension.