integrally moulded on a plastic shell member of the lower casing 320 the first and second receptacles are in communication and are communicable through an inter receptacle aperture 316 the inter receptacle aperture 316 is defined by a bridge member 318 which partitions the first and second receptacles as shown more particularly in fig8 the bridge member 318 is formed as part of a detachable component which is mountable on the lower casing 320 the bridge member 318 and the inter receptacle aperture are arranged such that the protruding adapter 130 of the bicycle computer module 100 is received within the aperture and latched by the bridge member in a closely fitted manner when the smart phone 160 is seated in the first receptacle and mechanically connected with the computer module as an assembly the assembly will sit squarely on the casing and will be latched in place by the bridge member 318 to promote water tightness closure taps shown more particularly in fig8 e and 8f for fitting onto the casing are provided so that different smart phone models could be accommodated an adapter pad 340 is provided this adapter pad 340 is moulded of a resilient material to provide protection to the smart phone since the operating conditions could be harsh to enable the assembly to be securely mounted on a support such as the handle bar of a bicycle and to facilitate convenient operation by a user a mounting clamp or bracket 350 as an example of a mounting means is formed on the bottom side of the lower casing the mounting bracket 350 also includes means for adjusting the inclination or elevation angle of the assembly with respect to a user.