Some 10,500 gardaí are to start wearing a new uniform, which will cost an estimated €5 million to fit out and supply, from this Friday.
Garda Commissioner Noel Conroy will introduce the uniform on Thursday. It includes a waterproof jacket, an inner "windstopper" fleece, and a new shirt with chevrons on the right sleeve for sergeants.
The amount of clothing allocated with the uniform has been described as "mean spirited" by the Garda Representative Association (GRA).
It says its members are to receive just four shirts - two for summer and two for winter - and two pairs of trousers, prompting hygiene concerns.
The cap will remain the same although there will be a new cap badge bearing the Garda colours.
The Garda Press Office said members will also wear a leather belt with brass buckle and Garda crest, Gortex safety boots, and a utility belt to hold handcuffs, baton and other equipment.
According to Dermot O'Donnell, president of the GRA, his members have been "making do" with the same uniform and clothes for three years. He welcomed the new uniform but added: "It is being done once again in a mean-spirited fashion that has become a hallmark of this Government's approach to Garda resources. Four shirts, and one pair of trousers for the relevant period is not good for personal hygiene, and would not be acceptable anywhere else in the public service."
The new uniform will not include a new "extendable" baton. These can reach up to 0.3m (18in), and have recently undergone Garda trials. The model used in the trials was found to be unsuitable.
Identity numbers for gardaí will remain detachable - but numbers will have to be worn on items of upper body wear, as is currently the case.
The new uniform was piloted by gardaí in two stations - Tullamore, Co Offaly and the Bridewell, Dublin, in June 2003.