19643 3 Step Under Platform Ladder – Fits universal swim platforms (Replaces [Data Needed])

$264.99 $423.00

Shipping calculated at checkout.

19643 3 Step Under Platform Ladder – Fits universal swim platforms (Replaces [Data Needed]) is backordered and will ship as soon as it is back in stock.

Worry-free returns

You may return most new, unopened items within 7 days of delivery for a full refund. We'll also pay the return shipping costs if the return is a result of our error (you received an incorrect or defective item, etc.).

You should expect to receive your refund within four weeks of giving your package to the return shipper, however, in many cases you will receive a refund more quickly. This time period includes the transit time for us to receive your return from the shipper (5 to 10 business days), the time it takes us to process your return once we receive it (3 to 5 business days), and the time it takes your bank to process our refund request (5 to 10 business days).

If you need to return an item, simply login to your account, view the order using the "Complete Orders" link under the My Account menu and click the Return Item(s) button. We'll notify you via e-mail of your refund once we've received and processed the returned item.

Delivery and Shipping

Free standard shipping on all orders under 1 KG

If you have any questions, feel free to email us at info@sierramarines.com, and we’ll get back to you within 20–36 hours.

Product Details

The Sea Sierra 19643 3 Step Under Platform Ladder is a versatile boarding solution designed for universal fitment on most swim platforms and pontoon boat decks. Constructed from electropolished 304 stainless steel, it offers excellent corrosion resistance in marine environments. Its telescoping design allows for compact and secure storage when not in use.

Installs conveniently under the swim platform or deck.
Features flat poly treads for comfortable and secure footing.
A spring-loaded mechanism locks the ladder securely in its stowed position.

Part Number Matrix

Use this matrix to confirm equivalent references across OEM and aftermarket.

Engine & Model Compatibility

Confirm your engine model/year in the table below.

This product is a universal marine ladder and is not specific to particular engine models. It is designed for installation under swim platforms or under the deck of pontoon boats, offering a broad range of compatibility with various vessel types.

Technical Specs

Housing Material: Electropolished 304 Stainless Steel
Housing Color: Metallic
Deployed Length: 85 cm (33.5")
Stowed Length: 41 cm (16")
Overall Height: 8 cm (3")
Width: 29 cm (11.5")
Support Frame Length: 37 cm (14.75")
Support Frame Width: 35 cm (13.75")
Fitting Type: Flat poly treads
Weight Capacity: Rated to 124.7 kg (275 lbs)
Mounting: Three 1/4" mount holes on each side, 6" spacing
Other Features: Nylon bushings between ladder sections for smooth operation; Spring-loaded self-locking for stowage

What’s in the Box

1 x 19643 3 Step Under Platform Ladder

Installation Notes

Position the ladder assembly in the desired location under the swim platform or pontoon deck.
Ensure there is adequate clearance for the ladder to fully deploy and retract without obstruction.
Carefully mark the six mounting hole locations on the mounting surface.
Drill pilot holes appropriate for 1/4" mounting hardware (not included).
Securely fasten the ladder using marine-grade 1/4" stainless steel bolts, washers, and locking nuts.
After installation, test the ladder's functionality, ensuring it deploys, retracts, and locks into the stowed position correctly.

Troubleshooting & FAQ

What type of boat is this ladder for?

This is a universal ladder designed for boats with swim platforms or pontoon boats with a suitable under-deck mounting area. It is not specific to any single boat brand or model.

How does the ladder stay stowed while underway?

The ladder features a spring-loaded, self-locking mechanism that automatically secures it in the retracted position to prevent it from deploying accidentally.

What hardware do I need for installation?

Installation requires six 1/4" marine-grade stainless steel bolts, nuts, and washers. Mounting hardware is not included due to the wide variety of platform materials and thicknesses.

What is the maximum weight limit for this ladder?

This ladder is rated to a maximum capacity of 124.7 kg (275 lbs) under normal use conditions.

How can I prevent corrosion and keep the ladder operating smoothly?

Rinse the ladder with fresh water after each use in saltwater environments. The 304 stainless steel is highly corrosion-resistant, and the nylon bushings ensure smooth operation with minimal maintenance.

OEM vs. Aftermarket?

This listing is an aftermarket replacement (not OEM). Built to OEM-level specifications with comparable materials. Manufactured in an ISO 9002 facility, batch-inspected for consistency.

Shipping speed & cost

We ship worldwide quickly—typical transit 5–15 days. Standard shipping is free; expedited options appear at checkout where available.

Warranty & returns

Covered by a 1-year warranty against manufacturing defects under normal use. If issues arise, contact support with your order details. Returns are accepted within our standard window (unused & in original condition). See our policy page or reach out for instructions.

Safety & Important Info

Verify images/specifications vs your original part. If anything differs—even if your model appears compatible—do not purchase.
This is an aftermarket replacement, not an OEM component.
Professional installation is recommended for safety and performance.

About Sea Sierra

Pro-Grade Standards — We supply marine parts engineered to OEM-level tolerances and tested for real-world conditions.
Fast Global Fulfillment — Free standard delivery to most regions in 5–15 days.
Manufacturer-Direct Value — Fair pricing without compromising on materials or QC.

Payment & Security

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