Model number is OS6609,The lock housing is made with zinc,and then covered with plastic ABS,Then tensile strength is more than 180kgs.it is made by ourseal company,this seals is made with three lock mechanisms on the pallets insert. the tube is just for the wire 1.5mm,the seals is safer. OURSEAL(R) is a famous brand of security seals in China,it is a creater of ISO17712.there are more on the ourseal's official web site.OURSEAL also produce high securit bolt seals compliant with ISO17712:2013,meter seals,plastic seals,cable seal,waterproof security bags and so on. you are welcome to cooperate with us at anytime.