National ceiling access panel. Convenient for maintenance and repair of wiring, plumbing, and air conditioning equipment in the ceiling space. ・Model number: CWT45WDE ・Ceiling opening dimensions: 456✕456 　★Cannot be installed in bathrooms. ・Inner frame ceiling material can accommodate up to 24mm thickness. ☆The cardboard box is crushed due to a long storage period, but the product inside is not damaged. Confirmed. Thank you for viewing.