Home / Shop / Fins / Mistral 7" and 9" GRP Honeycomb US Box Fins Mistral 7" and 9" GRP Honeycomb US Box Fins Mistral 7" and 9" GRP Honeycomb US Box Fins Mistral 7" and 9" GRP Honeycomb US Box Fins 9" Blue Honeycomb 7" Blue Honeycomb Quantity Add to cart Our simple 7” and 9” honeycomb GRP fins will remain weed free and provide the correct balance between directional stability and looseness that’s most desirable. Designed for 12’6 and 14’ boards, US Box fitment. Honeycomb GRP 7" or 9" US box fitment If you’re getting your iSUP out of storage after a long winter, it’s advised you take some time to do some basic maintenance checks at home. Inflate to recommended PSI If stored deflated check fold lines are OK Make a close inspection of the seams for any leaks Do same with the valve and re-tighten using the valve spanner Check fin box and fin fitment Check D-Ring connections Check deck pad Check for any discolouration due to bacteria Wash and scrub board with cool soapy water Observe for any ‘bubbling’ caused by leaks Make a note of PSI and leave for 48hrs Check PSI and note any lose of pressure Investigate any issues and address / fix For minor none seam leak issues fix using repair kit Seam failure often requires professional input Consider contacting inflatable boat repairers Pay safely with: