The present invention relates chromatography cartridge comprising a barrel to be sealed with a cap utilizing a seal member such as an O-ring. The barrel comprises barrel lip on the circular top surface of the barrel. The cap comprises a seal holder and a space to accommodate the seal member. Then the cap is mounted on the barrel an interior contact surface of the cap will contact the barrel lip and force the barrel lip to shear inwards. The barrel lip and the contact surface will form a first cartridge seal. The barrel lip will in turn contact the seal member which will contact a seal surface of the cap and the seal holder to form a second cartridge seal.