Canister TPM has been used to provide extra protection to non-combat ships in the fleet. The Canister TPM consists of a self-contained TPM-1 round and handling equipment bolted to the exterior of a ship and linked to a ship's own sensors (though once fired it uses it's own guidance only). With TPM-1 now considered obsolete NS has been working on an improved Canister TPM using some of the thousands of surplus TPM-2 sounds in storage.
Canister TPM-2 will replace existing installations during the next round of ship maintenance and updates. Around five hundred TPM-2s have been converted.
