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Interior Performance frame manufactured in a double rebated profile for optimal design appearance in 40/28 mm solid wood with 93 mm frame depth. The solid frame is manufactured with a special technique which results in a very durable and stabile construction which makes the frame a perfect fit for both commercial and residential use. The frame type can be used for unclassified doors as well as door sets with E30 and EI30 fire rating and 35dB sound reduction (Rw 38dB), cold and hot smoke classification, durability performance in heavy to severe duty and climate classification C1 (temp. 3-23 degrees C°).