Understanding the Contents of a Tested Design

hy do some items have an asterisk*? What does the asterisk mean? Can I specify a similar product even though it is not specified in the design?
Every tested design contains a series of item numbers. The following are examples of how to understand what the asterisk means when used or not used:

• Example A:
  “1. Nails – 6d cement coated nails 1-7/8 in. long, 0.0915 in. shank d…………………….”
  In this example there is no asterisk. Any nail meeting these specifications can be used.
• Example B:
  “4Q. Gypsum Board* – Any 5/8 in. thick, 4 ft. wide, Gypsum Board UL Classified for Fire Resistance (CKNX) eligible for use in…………………….”
  In this example the asterisk is used after ‘Gypsum Board”. Any gypsum board meeting these specifications AND bears the UL or ULC Certification Mark can be used.
• Example C:
  “8. Batts and Blankets* – Required for use with resilient channels, Item 7, min. 3 in. thick mineral wool batts, placed to fill interior of wall, attached to the nom 4 in. face of the studs with staples placed 24 in. OC.
  ROCKWOOL — Type SAFEnSOUND
  The asterisk is used after “Batts and Blankets” AND “Rockwool (manufacturer name) – Type SAFEnSound” (product name) precedes the item specification. In this case, the Rockwool product (bearing the UL or ULC Certification Mark) must be used, substitutions are not allowed. Rockwool is a sponsor of the test.