The Bremont Longitude is new for 2021. It is the first Bremont to be powered by an ENG300 series movement, which is largely manufactured and assembled in Bremont's own The Wing facility. Dubbed the ENG376, this movement displays the hours, minutes, small seconds, big date, and power reserve. It features a silicon escape wheel and pallet, plus a free sprung hairspring. The rotor is made of solid tungsten.

The case of the Bremont Longitude measures 40mm across at a height of 12.5mm. It is fitted with the brands signature Trip-Tick construction for enhanced shock protection. The dial has a raised globe with debossed longitude lines. Also incorporated in the watch is original brass from the historic Flamsteed Meridian Line at the Royal Observatory Greenwich, London.