They are also known as the black truss markings. They provide a quick visual for the tape user and speed up the measuring process. Originally, 19.2 inches was used in metric layouts. Dividing 5 into 96 inches (8 feet) gives 19.2 inches, which yields five trusses per sheet. The black arrow in the photo to the right points directly at the black diamond located on 19.2. The red stud markings every 16 inches allow for a standard layout of six studs per 8-foot (96) section.
1 Minors under 18 must be accompanied by an adult at all times in the range and store. 2  You must be 21 years old to shoot a handgun & 18 years old to shoot a long gun without being accompanied by a parent or legal guardian.
Shooting range. A shooting range or firing range or archery range or pistol range or rifle range or shooting gallery or shooting ground is a specialized facility designed for archery or firearms practice. Each facility is typically overseen by one or more supervisory personnel, called variously a range master or Range Safety Officer (RSO) in the US, or a range conducting officer (RCO) in the UK.