
Sea-Dog 290901-1
Conventional 90-degree universal tee. Check for a one-piece rail connection; it is not the hinged version.
Sea-Dog 290901-1 and 290904-1 both connect 1-inch outside-diameter marine rail at a right angle, but the joining styles differ. The universal model is a conventional tee, while the hinged tee can open around an existing tube. Use this reference to identify the correct fitting before replacing a rail component.
290901-1 is a conventional 90-degree universal tee for 1-inch tubing.
290904-1 is a hinged 90-degree tee for 1-inch tubing.
Both use 1-inch tube OD and investment-cast 316 stainless. The 7/8-inch equivalents have different MPNs.
Sea-Dog references replaceable 299999-1 set screws and a 1/8-inch Allen wrench. Check included hardware on the listing.
| Part number | Style | Tube OD | Material | Assembly |
|---|---|---|---|---|
| 290901-1 | 90° universal tee | 1 inch | 316 stainless steel | Conventional |
| 290904-1 | 90° hinged tee | 1 inch | 316 stainless steel | Hinged |
Sea-Dog specifies a 0.049-inch stainless tube wall reference. The manufacturer's handrail tee range includes set screws where appropriate; replacements are identified as 299999-1. A 1/8-inch Allen wrench is specified for installation. Match the original rail design before ordering.
Each product is linked by exact manufacturer part number. Check the item's condition and contents before ordering.

Conventional 90-degree universal tee. Check for a one-piece rail connection; it is not the hinged version.

A 90-degree hinged tee designed for 1-inch tubing. Confirm the hinge rather than relying on the stainless appearance.
Sea-Dog rail base identification · Sea-Dog Bimini end fittings
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