Identify Attwood Lock'N-Pin 67729, 6773 & 67739 Seat Bases

Trying to identify an Attwood seat pedestal base removed from a boat? The Lock'N-Pin 3/4-inch family includes threaded and non-threaded sockets with different materials, sizes and installation depths. Identify the original part number and how the post engages before selecting a replacement.

Find a matching base by number, size and socket

The first six models use 7 × 7-inch plates. The two SP-numbered rectangular fittings serve different deck footprints: SP-64839 is 4 × 8 inches and SP-66839 is 6 × 8 inches. Check their individual mounting drawings before cutting the deck; the rectangular plate size is not the cutout size.

What to inspect on the original base

1. Find stamped markings. Record the complete Attwood number, including any “-T” suffix. A similar square plate can hide a different socket.
2. Check whether the post screws in. Threaded and non-threaded Lock'N-Pin bases require the correct post style; matching the pin-system name alone is insufficient.
3. Compare the plate shape. Identify 7 × 7-inch square versus 4 × 8 or 6 × 8-inch rectangular hardware, including fastener positions.
4. Measure the opening and clearance. Compare the original cutout with the exact part specification. Do not equate the “3/4-inch” Lock'N-Pin name to the deck-hole diameter or post-tube outside diameter.
5. Check the seating position. The featured bases are Type B hardware and are not intended for helm or driver seating; do not combine unrelated seat components without manufacturer confirmation.
6. Read the individual listing. Confirm condition and available components before ordering, particularly if replacing hardware removed from an older boat.

Attwood base listings with product photos

Open the exact MPN below to check the current listing, condition and availability. These particular catalog listings are marked Brand New, even though they appear on UsedRVParts. Eligible parts may be viewed or picked up in Kelowna by appointment.

Attwood 67729

Non-threaded · Zinc-plated steel

7 × 7-inch base plate

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Attwood 67729-T

Threaded · Zinc-plated steel

7 × 7-inch base plate

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Attwood 6773

Non-threaded · Stainless-steel finish; steel lip tube

7 × 7-inch base plate

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Attwood 6773-T

Threaded · Stainless-steel finish; steel lip tube

7 × 7-inch base plate

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Attwood 67739

Non-threaded · Stainless-steel finish; steel lip tube

7 × 7-inch base plate

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Attwood 67749

Non-threaded · Clear-coated aluminum

7 × 7-inch base plate

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Attwood SP-64839

Non-threaded · Stainless-steel finish; steel lip tube

4 × 8-inch base plate

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Attwood SP-66839

Non-threaded · Stainless-steel finish; steel lip tube

6 × 8-inch base plate

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Other Attwood seating systems

Does your removed pedestal use the larger 2-3/8-inch post system? Refer to our Attwood 238 Series seat-mount identification guide before selecting a base. Lock'N-Pin and 238 Series parts must not be assumed compatible.