3/8" Thick 4" OD Round Aluminum Countersunk Pad | 4 Countersunk Holes + Center Vent | Marine Grade 6061-T6
Part Number: 0050
Four-Hole Round Countersunk Pad with Center Vent
Precision CNC-machined 6061-T6 aluminum round countersunk pad with four mounting holes and a 5/16" center vent. Designed for flush-mount fastening on fiberglass deck surfaces in saltwater marine environments. Four countersunk outer holes allow screw heads to sit flush with the pad surface, while the center vent provides weld gas release during installation.
| Material | Marine Grade 6061-T6 Aluminum |
| Outside Diameter | 4" (101.6 mm) |
| Thickness | 3/8" (0.375") |
| Mounting Holes | 4 countersunk (5/16" dia. for 1/4" fasteners) |
| Center | 1 vent hole (weld gas release) |
| Shape | Round |
| Finish | Matte — tumbled, deburred, paint/powder coat ready |
| Weight | 0.44 lb |
Common Applications
T-tops, tuna towers, hard tops, radar arches, leaning posts, grab bars, bow rails, outrigger mounts, rod holders — any fiberglass or aluminum deck requiring flush-mount hardware.
Frequently Asked Questions
What does "countersunk" mean for this pad?
Countersunk means the mounting holes are chamfered so countersunk head screws sit flush with the pad surface — no protruding screw heads that could snag lines or cause injury.
What is the center vent hole for?
The center vent hole allows trapped air and gases to escape during welding, preventing blow-through and ensuring a clean, full-penetration weld.
Can this pad be used on a fiberglass deck?
Yes — this pad is designed for fiberglass deck installations. The countersunk holes accommodate countersunk head screws, and the pad distributes fastener loads over a wider surface area to prevent deck damage.
What size fasteners do I need?
The four countersunk holes are sized for 1/4" fasteners (5/16" hole diameter). Use 1/4"-20 stainless countersunk head screws for best results.
- Local pickup available
- One Business Day Shipping
- Call us Mon.-Fri. 9:00 a.m. to 4:00 p.m. if in any doubt.
Due to this item's size and weight we can only ship it in an economical way via Less Than Truckload (LTL) consolidated land shipping, and only to the contiguous 48 States.
For shipping inquiries to AK, HI, PR, US-VI, and international shipping, please contact us first at sales@weldingworldinc.com.
All of the destinations above we can only serve as a Free Carrier (or FCA) modality, that requires the customer to contract and pay for their carrier service of choice. We can still ship the item, but only to a warehouse/receiving office within the 48-contiguous States.
In plain terms what this means is that if you want to ship your product to any non-contiguous US territory or internationally, you, the customer, has to provide us with the warehouse address of the carrier that serves your locality with an address within the contiguous 48-US States, as we do not ship overseas on our own.
