For bottle size, add to part number:
-00 System less bottle
-05 System with 5lb bottle
-10 System with 10 lb bottle
-12 System with 12lb (Composite) bottle
-15 System with 15lb bottle
MainLine Carbureted Nitrous Systems

(Click links for more information)

MainLine Carbureted Nitrous Plate System
PN: ML1000 Holley Plate
PN: ML1001 Dominator Plate
PN: ML1002 Q-Jet/Spreadbore Plate
Horsepower: 100-250whp

MainLine SportComp Direct Port Nitrous System
PN: ML4000
Horsepower: 100-500whp