Thank you for viewing. This is a parasol vise used for crucian carp fishing. The support post insertion opening is approximately 10mm. This is a used item, so there are some minor scratches, dirt, and rust, but there are no functional problems and it is a vise that can be used normally. The condition of the exterior may be difficult to understand, but please check the photos. To prevent trouble, please ask any questions before purchasing. If you are interested, please consider it. Please check the photos before purchasing.