P.S.S. Packless is the way to go. You need to measure the prop shaft and the log to know what size to order. The hose is connected to cool and lubricate the interface between the stainless steel piece that pre-loads and the seal that attaches to the log.

When you replace it pays to not only align the coupler but the prop shaft in the log as well. If the shaft is not centered the stainless piece will not meet the log seal squarely and can cause premature wear to the log seal.