Steam Manzanillo. Full strike of oval handstamp with May 6, 1865 double cds of San Francisco, Cal. (Williams SAF-600) on incoming cover from Colima, Mexico, correct double rate of 20¢ with manuscript blue crayon "20" due marking, bold oval Colima origin postmark (Colima is approximately 50 miles inland from the port of Manzanillo), reverse with matching "3" reales rate handstamp; cover with rebacked edge wear, Fine, still a choice strike of this rare steamship route marking. Estimate  $1,000 - 1,500. $0 (Image)