Pressure Indicating Cap Item No.:NS2005-M, the first cap.One cap indicates one PSI. Pressure selection 26,28,30 & 60 psi.Item No.:NS2009-P, the second cap.One cap fits for any tire pressure covering 20-42 psi.Item No.:NS2005-P, the third cap.One cap indicates one PSI.Pressure selection 26,28,30 & 60 psi. Pressure Indicating Cap