1 Liter of pretreatment + 3 liters of water makes = 1 Gallon
1 Gallon+ 3 gallons of water makes = 4 Gallons
Light shirt pretreatment is for when you are NOT printing with white ink. This is usually the case when printing on white shirts. If you are printing on light colored shirts and NOT using white ink, then this is still the pretreament you want to use. What this does is make your designs crisper, more vibrant and It doesn't leave a yellow stain like dark shirt pretreatment can.