Carriage Bolt Seat

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This is a versatile assembly that securely holds a 1/4 - 20 carriage bolt in place. It accommodates #6 wood screws and countersunk heads with ease. If you have a square-hole drill bit of the right size to prevent the carriage bolt from rotating, then this seat might not be necessary. In this case, the cap will function independently, but you'll need to carefully mark the pilot holes for the screws after drilling the square hole. This way, you can use the carriage bolt head as a guide to position the cap correctly. Keep in mind that if you choose to use this assembly with the plastic seat, you may not be able to achieve maximum torque on the carriage bolt. In such cases, thumb wheels or wing nuts might be your best option.