For Canon EF 70-300mm f/4-5.6L IS USM. For Canon EF 28-300mm f/3.5-5.6L IS USM. 1 x Lens Tripod Mount Ring. Ring width: 18mm. Ring thickness: 4mm. Quick release plate is AS 39mm standard, compatible with RRS / ARCA-SWISS / KIRK / WIMBERLEY / MARKINS / SUNWAYFOTO / KANGRINPOCHE / BENRO / SIRUI / MARSACE / ISHOOT ball head of Arca 39mm fit.
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