Greenfield Products Coated Navy Anchor - Red The Navy Anchor is a classic, proven design, which has been in use on large vessels and warships for over 100 years. Navy Anchor performance comes from the combination of weight and mechanical principle. Like all fluke anchors, chain is recommended for proper performance. Model Weight Recommended Boat Size In Winds Up To 30 Knots Chain Recommended Scope Line FeetDepth Feet 910-RD 10 lbs Up to 14 feet 14 x 4 71 915-RD 15 lbs Up to 18 feet 14 x 4 71 920