Warm Notice: this utility key is not suitable for some kind of radiator, please make sure its size is match your device before you buy Size: the metal train key is approx. 7.2 x 7.2 x 1.3 cm/ 2.83 x 2.83 x 0.51 inches, standard size for gas box, meter box, water box, elevator and so on 4 Shapes: the metal cross key includes 2 square shape utility key, 1 triangle water meter key and 1 key shape gas meter key, 4 shapes in total Wide application: the 5-way key can open the toolbox doors, electric doors, especially suitable for the doors and windows of public places Common use: the water key can open many things so long as accord with its size and shape; It is multifunctional, also can be the practical wrench to turn screws