I have kept this item unused. I purchased several of these for making #5-6 rods, but the inner diameter was too small to fit the #6 blank I had, so I widened the inner diameter myself from 9.5mm to approximately 10mm. The wooden part of the seat has a thick structure to begin with, so I don't think it will affect the strength, but please refrain from purchasing if you are concerned. Seat length: 103mm, weight: 20.7g, seat outer diameter: 18.0mm, seat hole inner diameter: approximately 10mm, diameter of the upper end of the reel seat to be embedded in the grip: 21.0mm, with end cap. I think it will fit a 9-foot #5-6 single-hand rod. Please note that there are minor scratches due to storage, etc.