A sterilization cassette has a slide latch system to secure the lid of the cassette to the body of the cassette. A finger tab on the outside of the cassette moves a latch arm on the inside of the cassette along a slot. A tension spring secures the position of latch components whether the latch is open or closed. Spacers between the cassette and latch parts facilitate smooth gliding action. The latch arm engages an angled bracket on the lid of the cassette. Alternating notch depths on instrument rails within the cassette work with opposing rails that likewise have alternating depths of notches to capture and hold instruments. This notch configuration causes the handles of adjacent instruments stowed in the cassette to stagger in height so that a clinician can access the handles of the stowed instruments.