[VERY EASY TO SET]: The way you set them up is just pinch the back like a clothespin and you're done,It's pretty much impossible to hurt yourself setting these up,Bating is done through a removable trap door and the Food trough is recessed so it won't be easily takenThey're extremely sensitive. [EASY TO FILL]: It's so nice to not have to be concerned about putting food in the Food trough. a small, removable Food trough is accessible with a quick twist to remove, and screw back in from underneath. Then carefully placing in the right location, and squeezing to set it is all that it takes. Make sure you keep your fingers away from the pointed front. [REUSABLE and DURABLE]: use of ABS,long-term use not easy to break,washable material, easy to clean and remove the odor that appeared during the previous use,so that your home can reduceintruders.High strength plastic ABS+PS+steel wire. [VERY EASY TO RELEASE AND RESET]: without touching the results or toothed part. and best part no need to touch just press and itll drop the result, amazing product. Size: Small: 11.2*4.8*5.6cm/4.41*1.89*2.21 inch Large: 14*7.5*7.3cm/5.51*2.95*2.87 inch Small: the initial clamping force of the spring is 0.6KGS, the maximum elastic force is 0.8KGS, and the firing sensitivity is 20-25G Large size: the initial clamping force of the spring is 1.4KGS, the maximum elastic force is 4.1KGS, and the firing sensitivity is 20-25G