(2)Where an offender is sentenced to field punishment No. 1, he may, during the continuance of his sentence unless the Court-Martial or the officer, as the case may be, otherwise directs, be punished as follows:-(a)he may be kept in irons, that is to say, in fetters or hand-cuffs or both fetters and hand-cuffs, and may be secured so as to prevent his escape,(b)when in irons, he may be attached for a period or periods not exceeding two hours in any one day to a fixed object, but he must not be so attached during more than three out of any four consecutive days nor during more than twenty-one days in all.Explanation 1.-The offenders must be attached so as to be standing firmly on his feet which, if tied, must not be more than twelve inches apart and it must be possible for him to move each foot at least three inches. If he is tied round the body there must be no restriction of his breathing. If his arms or wrists are tied, there must be six inches of play between them and the fixed object. His arms must hang either by the side of his body or behind his back.Explanation 2.-For the purpose of this punishment, irons should be used when available, but straps or ropes may be used in lieu of them when necessary. Any straps or ropes used for the purpose must be of sufficient width to inflict no bodily harm, and leave no permanent mark on the offender,(c)he may be subjected to the like labour, employment and restraint and dealt within like manner as if he were undergoing a sentence of rigorous imprisonment.