What is the difference between Type I and Type II 6th-generation bonding agents?

The 6th-generation (Type I) bonding agent [Clearfil PROTECT BOND (Kuraray America)] has a hydrophilic self-etching primer in one bottle and a bonding resin in a separate bottle. The two components are placed on the tooth in two separate steps. With the 6th-generation (Type II) bonding agent [XENO III (DENTSPLY Caulk)], the primer and bonding resin are in two separate containers, but are mixed and placed on the tooth in one step. The 6th-generation (Type I) bonding agents are less technique-sensitive and provide predictable bond strengths.