Part Number: 0175
Three-Hole Oblong Backing Plate
Precision CNC-machined 6061-T6 aluminum oblong backing plate with three 21/64" countersunk holes sized for 5/16" fasteners.
| Material | Marine Grade 6061-T6 Aluminum |
| Dimensions | 10" × 5.5" (L × W) |
| Thickness | 3/8" (0.375") |
| Mounting Holes | 3 countersunk (21/64" dia. for 5/16" fasteners) |
| Shape | Oblong |
| Finish | Matte — tumbled, deburred, paint/powder coat ready |
| Weight | 1.745 lb |
Common Applications
Under-deck reinforcement for through-bolted marine hardware, seating, and structural mounting where a three-hole backing plate is needed.
Frequently Asked Questions
What fasteners fit the countersunk holes?
The three countersunk holes are 21/64" diameter and sized for 5/16" fasteners.
What is a backing plate used for?
A backing plate distributes load beneath a mounting surface and reinforces the surrounding structure.
What are the finished dimensions?
This oblong backing plate is 10" × 5.5" and 3/8" thick.
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.
Welding World Inc. | ABYC, NMMA & USCG Certified Marine Manufacturer
Address: 12940 SW 122nd Ave, Miami, FL 33186
Phone: (305) 778-1221 | Email: sales@weldingworldinc.com
Hours: Mon–Fri: 8:00 AM – 4:00 PM | Sat–Sun: Closed
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