All-Weather Bait Blocks - 30 Pack from The Big Cheese are moisture resistant poison bait blocks which act as a mouse and rat killer. Simply place in a bait box (The Big Cheese Rat and Mouse Bait Station STV179 is recommended) where rodent activity is seen and the rodents do the rest. Both rats and mice are attracted to the bait, thinking it is food and once eaten, they are poisoned and will die. The ready-to-use bait is suitable for indoor and outdoor use and stays fresh in damp or wet weather. The blocks are universal - so fit all bait stations and can be fixed using a wire or rod. Please note the rodent will not die instantly. It will need to eat a significant amount in order for the poison to work. Contains difenacoum. Protect bait points from non-target animals and from water.