Miracote MiraPatch LM 7046 50 lb Bag Lath Mortar. MiraPatch LM is a two-component, polymer-modified, cementitious underlayment and embedment mortar specifically designed for the encapsulation of expanded metal lath reinforcement when installing Miracotes MiraFlex II Decking System over plywood substrates. MiraPatch LM is also suitable for use as an underlayment for tile, carpet and other flooring finishes, or when repairing, leveling and re-sloping concrete and other types of surfaces.