DIN471 Retaining rings for shafts (external), circlips.
Metric DIN 95 Oval (Raised Countersunk) Head Slotted Wood Screws are the preferred fasteners used to attach wood to wood or hardware to wood.
Metric DIN 471 External Retaining Rings (aka circlips) are thin, circular, metal stampings that are used to prevent movement between mating components. These are designed to be assembled axially onto a shaft and to be fit into a groove on the outside of the shaft. They function to reduce vibration and maintain proper position of two parts in an assembly and permit easy disassembly of the components by removing the retaining ring.