The iron nails of Roman crucifixion. Appears only in John 20:25, in Thomas' demand for proof of the resurrection.
Hēlos carries the weight of the atonement. Thomas: 'Except I shall see the print of the nails...' The risen Christ still bore the nail-marks — His glorified body retained evidence of suffering. Resurrection does not erase the cross; it transforms it. The wounds become credentials. Thomas utters the highest Christological confession: 'My Lord and my God.'