Stern of SC 93, Corfu, Greece. G. S. Dole Collection. 
This photo of SC 93 in dry dock shows a steel cable skirting the vessel, attached to blocks spaced around the perimeter of the chaser. Research suggests that this device was a towing harness used during the voyage overseas to the base at Corfu, Greece. It doesn't appear in photos taken during active ASW operations at Corfu. 
Stern view of SC 93 on the ways 
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