#1 - API RP1004 & EN 13083 Maximum Nose Size
This gauge is at the upper tolerance of the standard. If this gauge does not fit over, loading couplers may not connect.
#2 - API RP1004 & EN 13083 Nominal Nose Size
This gauge is at the mid tolerance of the standard and indicates a nosecone in the ideal working condition.
#3 - API RP1004 & EN 13083 Minimum Nose Size
This gauge is at the lower tolerance of the standard. If this gauge fits over, the nosecone has worn outside the standard.
#4 - Half Worn -Recheck Regularly
This gauge indicates a nosecone with 0.4mm wear beyond the lower tolerance of the standard. It is possible for a coupler to disengage itself from a nosecone of this siz
#5 - Worn -Replacement Recommended.
This gauge indicates a nosecone with approx 0.8mm wear beyond the lower tolerance of the standard. It is not uncommon for a coupler to disengage itself from a nosecone of this size