Summit Tksm30 Is A Trim Kit Designed For Use With Microwave Smbi27. It Ships With A Bottom Duct, Two Rails, A 30" Wide Trim Kit Frame, And All The Necessary Screws For Installation. This Trim Kit Can Be Combined With Microwave Smbi27 Or Units With Identical Dimensions. For The Same Kit Designed To Fill 27" Wide Spaces, See Model Tksm27.