Reformed Umayyad silver dirhems do not name the Caliphs, but the coin are dated which tells us under which Caliph they were struck.
Denomination : Silver Dirhem. Mint : Wasit.
Date : AH 119 (AD 739)
Reference : Mitchiner Islamic - 60 variety.
Size : 27.9 x 28.3 mm. Weight : 2..96 grams.
Grade : XF, with an attractive toning.
Obverse and Reverse : Arabic inscriptions.