Dam! I've been doing hair for 42 years and Hair Replacement for 32... I've dealt with most of the Manufactures & Distributors in the Country, I have over 75 types of base samples on hand and I've never heard of 64# nor 18# microlace.... I've dealt with several microlace's, but your terms seem to be something someone has given their own name too. But I'm glad you were impressed.