Bait cup keeps trap permanently baited. Able to access bait cup from the top of the cage. Rats enter and are unable to exit. Access door in the back wall of trap for release. Comes w/carrying handle. 8" W x 7 1/2" H x 17" long. Front opening 2 1/2" W x 3 1/4" H. Place trap along rat runway. Rats can be suspicious of new objects. Bait and leave alone for a few days.