The iButton Probe provides the electrical contact necessary for the transfer of data to and from the DS19xx family of iButtons. The round probe shape provides a self-aligning interface that readily matches the circular rim of the iButton’s MicroCan package. Metal contacts resist wear and are easy to keep clean. Ibutton Probe Application 1.Access Control /Hotel, Smart community, Fire alarm control;Swimming pools,water patrol,field work is extremely humid environment. 2.Work-In-Progress Tracking 3.Tool Management /Fleet management /Commercial cash registers 4.Inventory Control.