Gardai have released pictures of the body found in a suitcase dumped in Dublin's Royal Canal two weeks ago, along with items of clothing, to try to establish the man's identity.
The release of the picture and clothing is "an unusual step", say gardai, who add that they have no idea of the man's identify or where he came from, so this release was the "next step".
A "key item" among the deceased man's clothing is his leather jacket, described as "distinctive" - worn thigh-length, tan coloured, with two breast pockets with missing buttons and two waist pockets with missing buttons.
Contact with Interpol has also failed to establish his identify. Gardai do not yet know if the man is Irish or foreign.
They hope the pictures and the clothes will jog memories, including people in the rental accommodation sector.
The dead man's face is bloated from being in the water. Gardai investigating the murder say they believe the body may have been in the water for up to three weeks.
A post-mortem examination found he died of head injuries.
The man was five feet, 10 inches, of medium build, aged between 25 and 40, weighing about 10 1/2 stone, with brown wavy hair, and two tooth crowns fitted in his upper jaw. He was wearing a long-sleeved navy V-neck top and beige trousers.
Two teenage boys found the body inside a black nylon suitcase at about 7 p.m. on July 20th.