Bottom is 39mm RRS / Arca-Swiss fit quick release plate feature, compatible with RRS / ARCA-SWISS / KIRK / WIMBERLEY / MARKINS / SUNWAYFOTO / KANGRINPOCHE / BENRO / SIRUI / MARSACE / ISHOOT standard tripod head clamp, suitable for IS-JZ30 / IS-JZ50 / IS-JZ64 / IS-QJ58 / IS-QJ64 / IS-JZ60BK / IS-70BK / IS-JZ80BK etc.
eBay