Praise be to Allaah.
We put this question to Shaykh Muhammad ibn Saalih al-‘Uthaymeen, may Allaah preserve him, who answered as follows:
This is allowed on two conditions:
That it is not an extravagance on the part of one who cannot afford to wear this kind of jewellery
That it should not cause any kind of fitnah (temptation), such as the man being young and perhaps causing fitnah by wearing it.
The basic principle with regard to clothing is that everything is permissible except gold rings, which are haraam for men as is well known. And Allaah knows best.