I'm compiling a list of built-in lockoff enhanced infant, convertible and combination seats. Please feel free to reply and add names, especially of new models or those that aren't widely sold.
Also, if the model has lockoffs only in some trim levels, please mention the levels or names that do have built-in lockoffs.
Britax Chaperone
Britax Companion (discontinued)
Combi Shuttle (discontinued) and Shuttle 33
Chicco Keyfit 22/30
First Years Via
Graco Snugride 32, Snugride 35 and Safeseat 1
Safety 1st onBoard 35 (base only, 4-35 pound versions)
Orbit Baby Infant base (Strong Arm)
Teutario T-32 and T-35
Mia Moda Viva and Viva Supreme (recalled/discontinued)
Compass Infant (discontinued)
Britax Marathon, Marathon 65 and Marathon 70
Britax Boulevard, Boulevard 65 and Boulevard 70, Boulevard 70 CS
Britax Advocate CS, Advocate 65 CSand Advocate 70 CS
Britax Roundabout 55
Britax Roundabout (original 40 pound version, discontinued)
Britax Diplomat (discontinued)
Combi Coccoro (lockoff attachment)
Combi Zeus Turn (discontinued) and Zeus Turn 360
First Years True Fit, True Fit Premiere and True Fit Recline
Graco CozyCline and Graco Safeseat 2
Orbit Baby Toddler
Recaro Pro Ride
Recaro Signo and Signo G2
Recaro Como and Como G2
SafeGuard Child Seat (discontinued)
Graco Nautilus Elite
Recaro Start
Also, if the model has lockoffs only in some trim levels, please mention the levels or names that do have built-in lockoffs.
Britax Chaperone
Britax Companion (discontinued)
Combi Shuttle (discontinued) and Shuttle 33
Chicco Keyfit 22/30
First Years Via
Graco Snugride 32, Snugride 35 and Safeseat 1
Safety 1st onBoard 35 (base only, 4-35 pound versions)
Orbit Baby Infant base (Strong Arm)
Teutario T-32 and T-35
Mia Moda Viva and Viva Supreme (recalled/discontinued)
Compass Infant (discontinued)
Britax Marathon, Marathon 65 and Marathon 70
Britax Boulevard, Boulevard 65 and Boulevard 70, Boulevard 70 CS
Britax Advocate CS, Advocate 65 CSand Advocate 70 CS
Britax Roundabout 55
Britax Roundabout (original 40 pound version, discontinued)
Britax Diplomat (discontinued)
Combi Coccoro (lockoff attachment)
Combi Zeus Turn (discontinued) and Zeus Turn 360
First Years True Fit, True Fit Premiere and True Fit Recline
Graco CozyCline and Graco Safeseat 2
Orbit Baby Toddler
Recaro Pro Ride
Recaro Signo and Signo G2
Recaro Como and Como G2
SafeGuard Child Seat (discontinued)
Graco Nautilus Elite
Recaro Start