Supa-Kill Liquid Bait is for use when there is too much food competition and the rodent needs to drink. 
Rats need to drink otherwise they will dehydrate. Mice can extract moisture from the food it eats. It does not necessarily need to drink but should liquid be provided, they will drink.

Supa-Kill 1Lt Liquid PCO

Reg. No. SA: L5986 Act 36/1947

Effective against Warfarin resistant rats and mice, usually after a single feed.

Active Ingredient: Brodifacoum (anticoagulant)   2.5 g/ l

For use by registered pest control operators only, Liquid Bait.

Controls: Roof rats, Norway rats and common house mice.