The proper screws include special locking features to prevent the monitor from coming loose during transport, so standard off-the-shelf fasteners are not recommended. The following service kits are available through Philips:
PH-0058-73 (Philips # 989803195531 A) for SureSigns monitors
PH-0058-74 (Philips # 989803195541 A) for Efficia monitors