Uniform Random Timer in JMeter

Uniform random timer is one of the Jmeter timer which is used to generate fixed+random amount of time delay between 2 requests.

Total amount of delay = Random Delay Maximum + Constant Delay Offset

Random Delay Maximum : This is outer boundary limit of random time delay. It will decide maximum random pause time.
Constant Delay Offset : This is the fixed delay time which will be added in random delay.
For Example:
Random Delay Maximum = 3000 milliseconds and Constant Delay Offset = 7000 milliseconds. That means it will put random delay between 7 seconds to 10 seconds between two requests.