3/8" Thick 5.125" OD Round Aluminum Mounting Pad | Tapped 5/16"-18 UNC Center | Marine Grade 6061-T6
Part Number: 0004
Single-Hole Round Mounting Pad
Precision CNC-machined 6061-T6 aluminum round mounting pad with a tapped 5/16"-18 UNC center hole. The threaded hole accepts a bolt directly — no nut required — making this pad ideal for standalone mounting points on fiberglass deck surfaces. Commonly used on top or through the side of a deck pedestal, as well as through the fiberglass skin of a hardtop or T-top. Distributes fastener loads over a wider surface area to prevent damage to the fiberglass.
| Material | Marine Grade 6061-T6 Aluminum |
| Outside Diameter | 5.125" OD |
| Thickness | 3/8" (0.375") |
| Center Hole | Tapped 5/16"-18 UNC (accepts bolt directly) |
| Shape | Round |
| Finish | Matte — tumbled, deburred, paint/powder coat ready |
| Weight | 0.69 lb |
Common Applications
T-tops, tuna towers, hard tops, radar arches, leaning posts, grab bars — used as a mounting pad where a threaded receiver point is needed on top or through the side of a deck pedestal, or through the fiberglass skin of a hardtop or T-top.
Frequently Asked Questions
What is a mounting pad?
A mounting pad has a tapped (threaded) center hole that accepts a bolt directly — no nut required. It sits on the outside of the fiberglass surface and the bolt threads into the pad from behind, providing a clean, secure mounting point while distributing fastener loads to prevent damage to the fiberglass.
What does "tapped" mean?
Tapped means the hole has internal threads cut into it (5/16"-18 UNC in this case) so a bolt screws directly into the pad. No separate nut is needed — the pad itself is the threaded receiver.
What size bolt do I need?
The tapped center hole accepts a 5/16"-18 UNC bolt. Use 5/16"-18 stainless hardware 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.
