Sea-Dog Gas Filled Lift Spring 321489-1 - 90 lb, 20 Inch Extended Length, Marine and RV

The Sea-Dog Gas Filled Lift Spring 321489-1 is a 90 lb force gas spring built to marine OE standards for holding hatches, doors, and lids open safely and smoothly. It extends to 20 inches and compresses to 12 inches, giving an 8-1/8 inch stroke that suits engine and access hatches, tool boxes, golf carts, canopies, seating, RV doors, furniture, truck caps, and utility boxes. The spring features a hard chromium plated shaft for corrosion resistance and long service life, bronze bushings for smooth, low-friction operation, and polymer end fittings that accept a 10 mm ball stud. Its unique multi-lobe seal design offers superior sealing performance compared to standard single-lobe gas springs, reducing leak-down and extending usable life in marine and outdoor environments. This lift spring is rated for both marine (application code 1) and RV (application code 2) use, and Sea-Dog backs it with a 2-year warranty. Whether you are replacing a worn or leaking lift support or fitting out a new hatch or door, the 321489-1 delivers consistent 90 lb of lifting force with the fit and finish expected from marine-grade hardware.

Specifications

• Brand: Sea-Dog
• Manufacturer Part Number: 321489-1
• Force Rating: 90 pounds
• Extended Length: 20 inches
• Compressed Length: 12 inches
• Stroke Length: 8-1/8 inches
• Ball Socket Diameter: 18 mm
• Rod Diameter: 8 mm
• Ball Stud Size Accepted: 10 mm
• Application: Marine, RV
• Shaft Material: Hard chromium plated steel
• Bushing Material: Bronze
• End Fitting Material: Polymer
• Weight: 0.698 pounds
• Pack Quantity: 1 each
• UPC: 035514321976
• Warranty: 2-year Sea-Dog warranty

Fitment

Rated for marine and RV applications, including engine or access hatches, doors, tool boxes, golf carts, canopies, seating, RV doors, furniture, truck caps, and utility boxes. Accepts a 10 mm ball stud.

Frequently Asked Questions

How much force does the Sea-Dog 321489-1 lift spring provide? The Sea-Dog 321489-1 provides 90 pounds of lifting force, making it suited to heavier hatches, doors, and lids that need a stronger gas spring than the lighter-rated versions in the same lineup.

What is the extended and compressed length of this gas spring? The 321489-1 extends to 20 inches and compresses to 12 inches, giving it an 8-1/8 inch stroke.

Is the Sea-Dog 321489-1 suitable for RV use, or only marine use? Yes, the 321489-1 is rated for both marine and RV applications, along with tool box, canopy, seating, furniture, truck cap, and utility box uses.

What ball stud size does this lift spring require? The Sea-Dog 321489-1 accepts a 10 mm ball stud at its polymer end fittings.

What materials is the 321489-1 gas spring made from? It has a hard chromium plated shaft for corrosion resistance, bronze bushings for smooth operation, and polymer end fittings.

How much does the Sea-Dog 321489-1 weigh? The 321489-1 weighs 0.698 pounds.

Does the Sea-Dog 321489-1 come with a warranty? Yes, Sea-Dog covers the 321489-1 gas filled lift spring with a 2-year warranty.

What is the rod diameter and ball socket diameter on this part? The 321489-1 has an 18 mm ball socket diameter and an 8 mm rod diameter.

What is different between the 321489-1 and other Sea-Dog lift springs like the 321488-1? The 321489-1 is the 90 lb force version with an 18 mm ball socket and 8 mm rod, sharing the same 20 inch extended length and 12 inch compressed length as the 80 lb 321488-1, but delivering more lifting force.

What is in the box with the Sea-Dog 321489-1? Each 321489-1 gas filled lift spring ships as a single unit, one per package.

Can this gas spring be used on truck caps and tool boxes, not just boats? Yes, in addition to marine and RV applications, the Sea-Dog 321489-1 is designed to work on tool boxes, truck caps, canopies, and utility boxes.

Why does this lift spring use a multi-lobe seal instead of a standard seal? The multi-lobe seal on the Sea-Dog 321489-1 is designed to offer longer service life and more consistent performance than a standard single-lobe seal design.