An encasing for releasably containing a device and tire containing such encasing or encased device

An elastomeric encasement comprising a rubber patch (10) containing a cavity (11) to releasably hold a device (17) for use in assisting operation of a pneumatic tire (2) is disclosed. The cavity (11) is configured with an opening (13) to facilitate inserting the device (17) into and removing the device (17) from the cavity (11). The elastomeric encasement comprises an uncured or partially cured rubber composition. Also, an assembly comprising the elastomeric encasement and at least a portion of the device (17) within the cavity (11) is disclosed, as well as a pneumatic rubber tire (2) containing the elastomeric encasement or the assembly as a co-cured, integral, component of the tire (2).