This is an unboxed type 42 Batch 1 destroyer in the generic version which means there is no pennant.

These are rare now because of being made a good while ago but also because the radars are fragile and when the Batch1/2 were remade on cards the Batch 2 mould was used so the radar isnt correct. Length 4.8 inches and 115mm Code P 740 my ref P740generic. Just found three of these all unboxed and in good condition. Ref generic 42 1