Sea-Dog screw-out deck plates provide removable access to suitable boat compartments and service points. The four models compared here are UV-resistant ABS in either black or white, with two different flange diameters. Select the plate by opening dimensions and mounting layout, then choose the colour that suits your deck.
Two sizes, each available in black or white
Choose 337140-1 in white or 337145-1 in black. Both belong to the 4 7/16-inch nominal-opening group.
Choose 337160-1 in white or 337165-1 in black for the larger 6½-inch nominal group. Verify the cutout and available rim space.
Sea-Dog deck-plate manufacturer dimension chart
Sea-Dog identifies the nominal size as dimension A and the overall outside flange as dimension B. Dimensions C and D are additional installation measurements from the maker's diagram; confirm the exact drawing before making a deck cutout.
| Display MPN | Colour | A · nominal size | B · outside flange | C · drawing | D · drawing |
|---|---|---|---|---|---|
| 337140-1 | White | 4-7/16 in | 5-3/4 in | 4-1/2 in | 5-1/8 in |
| 337145-1 | Black | 4-7/16 in | 5-3/4 in | 4-1/2 in | 5-1/8 in |
| 337160-1 | White | 6-1/2 in | 8-1/8 in | 6-1/2 in | 7-3/8 in |
| 337165-1 | Black | 6-1/2 in | 8-1/8 in | 6-1/2 in | 7-3/8 in |
Dimensions in inches. These are Sea-Dog's manufacturer-labelled measurements for the exact display-pack MPNs; do not use a column as a cutting template without the maker's dimension drawing.
Mounting, sealing and maintenance
The molded ABS plates resist UV exposure and oxidation. Sea-Dog specifies six #8 flat-head mounting screws (not included) and silicone sealant on the hull or deck surface during installation. Choose appropriate supporting material and check the manufacturer's mounting diagram.
Sea-Dog instructs owners to clean screw threads with warm soapy water, lubricate with petroleum jelly or PTFE/Teflon grease, and avoid acetone or strong solvents. Do not force a crossed-thread lid. Confirm the existing cover's design before selecting a replacement.
These are inspection/access covers, not a substitute for a hatch designed to carry foot traffic or structural loads unless the installation is expressly approved for that use.
Sea-Dog screw-out access plate choices
Choose a colour and size below to see the product listing and availability.
Sea-Dog 337140-1
White ABS screw-out plate with a 5¾-inch outer flange for a correctly sized deck access opening.
View plate details and availability
Sea-Dog 337145-1
Black version of the 4 7/16-inch nominal access plate; check existing mounting holes.
View plate details and availability
Sea-Dog 337160-1
White screw-out access plate with an 8⅛-inch outer flange and larger opening.
View plate details and availability
Sea-Dog 337165-1
Black ABS access plate in the large 8⅛-inch outside-flange group.
View plate details and availabilityRelated marine deck fitting guides
NewRVParts products ship from supplier warehouses; viewing and pickup are unavailable.