On the bottom of this piece, what is the dimension between the lip that covers the stair nosing and the lip that abuts the laminate floor?

Pergo's answer is incorrect - That dimension is not provided. Their detail in Section 18 provides a dimension for the overall width of the piece (2 3/8", which is 2.37" and provided in the product description), the depth from the edge of the stair nosing to the edge of the laminate flooring (1 3/4"), and the clear space between the edge of the laminate and the lip of the molding (1/4"). It does not provide a dimension from the front of the nosing to the edge that rests against the stair nosing - which it the critical dimension that one needs in order to know how much to cut back an existing stair nosing in order for this nosing to be at the same dimension as the previous nosing.

Thank you for your interest in Pergo. The stairnose instructions are available on the Installation Essentials Guide on our na.pergo website. The dimensions can be viewed on the diagram shown under Section 18.