Combo set of all 13 sizes, Plastic restraining tubes STANDARD and LARGE STANDARD - Now there are 10 pieces instead of 9, in set ranging from 3/8’’ to 2’’ in diameter. Tubing is considered by many herpetologists to be the safest method of working closely with snakes during minor veterinary work. Comes with 2 end caps. LARGE - Sizes: 2-1/2", 3",3-1/2". A set for larger species of snakes. Tubes are utilized by slipping one end over the head and body of a snake until about half of the snake is inside the tube. The body is then grasped at the point where it exits the tube. One hand should hold the body of the snake and the tube simultaneously! This assures that the snake cannot back out of the tube. Tubes are used to increase the safety factor during probing or doing minor veterinary work. Comes with 2 end caps.