Here is some A2L Refrigerant Information (R454B and R32)
Refrigerant Cylinders or Tanks:

• Red Top
• Left-Handed Threaded Connection -Will Require adaptor for typical right hand threaded hose connection.  H28-936 QC-A2L-LH COUPLER QUICK
  LEFT HAND
• Pressure Relief Valve
• Flammable and Compressed Gas Labels

Transport Safety of R454B and R32:

• Cylinders Secured In Vehicle
• Outside Ventilation
• Fire Extinguisher 

Worksite Safety and Best Practices:

• Dedicated gauges and hoses
• Refrigerant leak detector for personal protection
• Electronic tools must be spark-proof
• Verify tools and equipment are safe for A2L Refrigerants (R454B and R32)