Under Platform Telescoping Sliding Ladder
- Under-platform telescoping boat ladder family with rubber-latch retention
- 3-step (B00301UPM), 4-step (B00351UPM), and 4-step 316 SS (B00351UPM-316) variants
- 304 stainless steel standard; 316 stainless option for saltwater service
- 35-1/4"–46-1/8" deployed length; 15-3/4"–16-1/4" stowed length
- 14-1/4" overall width; 10-1/8" center-to-center mounting on all variants
- Mounts under swim platform on bracket; telescopes down for use, retracts up for storage
- 400 lb weight capacity; ABYC H-41 compliant; accepts 1/4" flat-head fasteners
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The Under Platform Telescoping Sliding Ladder family covers the under-mount boarding ladder configuration with a rubber-latch retention mechanism. Unlike over-platform ladders that fold flat against the top of the swim platform, these ladders mount on a bracket under the platform, store telescoped up out of sight, and pull down for use. The result is a swim platform top free of visible hardware — favored on center consoles, express cruisers, walkarounds, and bowriders where deck aesthetics and clear walking space matter. All variants share the same 14-1/4" overall width, 10-1/8" center-to-center mounting hole spacing, 1/4" flat-head fastener size, 400 lb weight rating, and ABYC H-41 boarding-ladder compliance.
Picking the right variant comes down to freeboard and water service. The 3-step B00301UPM (35-1/4" deployed, 15-3/4" stowed) is the family's lower-freeboard option, suited to bowriders, mid-size center consoles, walkarounds, and express cruisers where three rungs reach the water. The 4-step B00351UPM (46-1/8" deployed, 16-1/4" stowed) is sized for express cruisers, center consoles 30 feet and up, walkarounds, and sportfishers — the fourth rung puts a step below the waterline on tall transoms where solo re-entry from the water requires the additional reach.
For boats in regular saltwater service, the B00351UPM-316 is the 4-step variant in 316 stainless steel for improved chloride and pitting resistance over 304. The mounting footprint is identical to the 304 4-step, so swapping between alloys is geometry-neutral. Mounting hardware is not included on any variant. Verify your existing center-to-center mounting pattern matches the 10-1/8" spacing before ordering as a direct replacement. Confirmed fitment across the family includes Barron Boats, Defiance Boats, Dorado Custom Boats, Hells Bay Boatworks, Highfield Boats, RH Aluminum Boats.
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Apply NowRETURN POLICY
We accept returns on most items within 30 days of delivery.
To start a return, submit a Return Authorization (RA) request using the form below. The RA must be issued within 30 days of the delivery date, and the item must be received back at our warehouse within 14 days of the RA being issued.
Requirements for a full refund include:
1. Item must be in new, uninstalled condition.
2. Item must be returned with all original packaging, hardware, and accessories.
3. Return shipping is prepaid by the customer unless the item arrived damaged, defective, or incorrect due to our error.
4. RA number must be clearly marked on the outside of the package.
NON-RETURNABLE ITEMS: The following are final sale and cannot be returned:
- Special order, built-to-order, or custom items
- Items cut, drilled, modified, or installed
- Items missing original packaging or accessories
- Items without proof of purchase
General - Cancellations, Shipping Damage, Missing Packages, Shipment Refusals:
Claims of shipping damage, incorrect items, or missing items must be reported within seven (7) days of delivery. For LTL freight shipments, damage must be noted on the delivery receipt at the time of delivery. Concealed damage claims after a clean signed POD are difficult to recover and may be denied by the carrier. Orders that have been processed and shipped cannot be cancelled, and you may need to wait until you receive the merchandise in order to return it. Customer is responsible for all costs associated with refused shipments including carrier fees, freight to the customer, and return freight. We reserve the right to refuse returns that are sent COD, without a return authorization, show signs of undisclosed installation/use, have missing parts/packaging, missing proof of purchase, or have SKU numbers that do not match our records. If you do not comply with any of the above conditions, we reserve the right to refuse the return/exchange, or to impose different or additional conditions.
Must Be Returned to the Following Address:
Marine Depot Direct
Returns Department
14716 Central Ave
Chino CA 91710
PARTIAL REFUNDS OR RESTOCKING FEES
| Condition | Refund |
|---|---|
| New condition, within 30-day window | 100% of the item price (less return shipping) |
| New condition, past 30-day window (case-by-case)* | 80% of the item price |
| Items that are damaged, missing parts, not in the original condition, or have obvious signs of use for reasons not due to our error | Up to 50% of the item price |
| Products that are unusable, destroyed, or incomplete to the point of no resale value | 0% of the item price |
*For most items, the return window is 30 days after delivery. LTL freight items, oversized items, and large hardware assemblies may be subject to an additional restocking fee to cover return freight and inspection. This will be disclosed when the RA is issued.
How Refunds Are Issued
If you're receiving a refund after we have received your item, it may take an additional three to five business days to process your return fully and issue your refund.
Once we issue your refund, it may take additional time for your funds to be made available in your account by your financial institution. See the following table for more details.
| Refund Method | Refund Time (After Refund Is Processed) |
|---|---|
| Credit card | Three to five business days |
| Debit card | Up to 10 business days |
| Checking account | Up to 10 business days |
In-stock items ship within 1 business day from our California or Florida warehouse. Items showing a lead time above ship once stock arrives at our warehouse.
> Same-day shipping on orders placed before 9:00 AM Pacific Time
> Standard ground delivery is 3-7 business days. Need it sooner? Choose Next Day Air or 2nd Day Air at checkout.
> Free shipping on U.S. orders over $99 (excluding AK and HI)
> Oversized items ship by LTL freight. Inspect the shipment and note any damage on the delivery receipt before signing.
> International shipping to Canada and other countries available at checkout
For full details, see our Shipping Policy.
