# 1.7.2 Buttons

There are four buttons at the bottom of the screen; their corresponding functions are shown on the lower edge of the screen: 

From left to right order of view: Button one: 

● Switch the interface. 

● Back to the previous level (the multi-level interface).

Button two: 

● When < ​is displayed: Returns to the previous option or interface; moves between choices after entering the interface.&#x20;

● When +​ is displayed: Edit the number.

![](https://2386771058-files.gitbook.io/~/files/v0/b/gitbook-legacy-files/o/assets%2F-LvhKtBvsv-DVMTySk5A%2F-LvhNORy-4vbvqJrZy9v%2F-LvhOFwtARmwBMJAsYQK%2F%E8%9E%A2%E5%B9%95%E6%8C%89%E9%88%95-1.png?alt=media\&token=6e8f49b1-cb0a-4cd8-99cc-6eae0a893ff6)

![](https://2386771058-files.gitbook.io/~/files/v0/b/gitbook-legacy-files/o/assets%2F-LvhKtBvsv-DVMTySk5A%2F-LvhNORy-4vbvqJrZy9v%2F-LvhOKK6B1cZASN24eaB%2F%E8%9E%A2%E5%B9%95%E6%8C%89%E9%88%95-2.png?alt=media\&token=8f23c658-4209-4cc8-a2b4-a46d60657761)

Button three:&#x20;

● Select the next menu or interface.&#x20;

● When editing numbers, jump to the next digit.

Button four:&#x20;

● When ENT​ is displayed: Press Enter to enter the selected menu.&#x20;

● When SET​ is displayed: Press to set the content entered.&#x20;

● When PAUSE​ is displayed: Press to pause measurement, Red light will flash.&#x20;

● When START​ is displayed: Press to continue measurement and release PAUSE​ status.

![](https://2386771058-files.gitbook.io/~/files/v0/b/gitbook-legacy-files/o/assets%2F-LvhKtBvsv-DVMTySk5A%2F-LvhNORy-4vbvqJrZy9v%2F-LvhOR3Lh5wlDkvB-cKo%2F%E8%9E%A2%E5%B9%95%E6%8C%89%E9%88%95-3.png?alt=media\&token=e07ca6af-a365-4388-a5bd-2b09e1c8411a)