2. Before cleaning, take the mask components apart according to the disassembly instructions. slot-mask tube uses a combination of the shadow-mask and aperture-grill technologies. Types of Monitors • CRT – Shadow Mask – Aperture Grille – Slot Mask • LCD Slot Mask • LCD – Passive Matrix – Active Matrix – TFT; 4. Once the headgear has been properly attached to the mask, follow the fitting tips below to fit the mask. How CRTs. Slot mask. Rather than the round perforations found in shadow-mask CRT displays, a. Soak and agitate the cushion, elbow and short tube in warm water. 1. Attach the pillows to the mask frame by inserting the top and bottom clips into the correct slots (shorter clip into. 5. slots and attaching it back to itself (Figure 1). Ensure the headgear band is not twisted. Shadow mask, which is made of small holes for the electron beam to pass through; Aperture-grill, a type of faceplate made of tiny vertical wires. . Help slow the spread of the virus with a beautifully-decorated face covering that features upgraded, adjustable ear loops and nose wire to ensure a great fit.