1.5". But it is very tight getting the rubber part on you will want to lube it up with soap. At least it was on our boat. The box I bought is Buck Algonquin and I think the model number is 00pb100x. They specify 1/4" packing but on our boat I could not get 3 rings in unless I was happy with only 2 threads of engagement on the nut, which I was not. So I just put 2 rings of Gore GFO in and it has been fine. Break in is critical with Gore packing if you go that route do it exactly as instructed, we have 1 season on it and it works very well. Splashed yesterday, 2nd season for the Gore, dripped a bit while moving to the slip then stopped dripping when the shaft stopped turning, as it is supposed to do.
1.5". But it is very tight getting the rubber part on you will want to lube it up with soap. At least it was on our boat. The box I bought is Buck Algonquin and I think the model number is 00pb100x. They specify 1/4" packing but on our boat I could not get 3 rings in unless I was happy with only 2 threads of engagement on the nut, which I was not. So I just put 2 rings of Gore GFO in and it has been fine. Break in is critical with Gore packing if you go that route do it exactly as instructed, we have 1 season on it and it works very well. Splashed yesterday, 2nd season for the Gore, dripped a bit while moving to the slip then stopped dripping when the shaft stopped turning, as it is supposed to do.
This is the part I bought but not from this site, example only:
[URL]http://www.deepblueyachtsupply.ca/drivetrain-hardware/packingboxes-compl...