For links with round or flat pins, just push out the connecting pins with a tack or removal tool. Then, remove the links and reinstall the pins to lock them in position. Irrespective of whether you've got a 1st era Apple Watch, the most recent Series 4, or anything at https://thebestrobotvacuum40516.dgbloggers.com/27197341/top-guidelines-of-parts-of-an-apple-watch-band