For double wheels central locking casters in past some years we only have 5 inch and 6 inch. Now in order to meet variety demand of clients we have developed 4 inch twin wheels central locking casters. Our 100mm twin central locking casters follow the same design as our 5 inch and 6 inch series casters, It ’ s can used on medical trolley. Nice design and PA hub with Germany origin Pu tread material ensure whole wheel have reliable quality. Mainly specs as below * Wheel frame use high quality Poly-amide * Wheel tread adopt German origin PU material --- Very durable * Wheel size:Ø100 x 65mm wide * Turning radius:29mm * Lock stem option: Ø32x50mm,Ø28 x 95mm * Dramatic Load capacity: 125kg/PC * Static load capacity:150kg/PC * Lock functional: Free,Total Lock,Direction Lock sales@casterwheelsco.com whatsapp: 0086-137 3645 4395