There are three varieties of pentagrids.

Initial type - 6A7 type (converter).

Grid 1 - oscillator grid,

Grid 2 - oscillator anode,

Grid 3 - screen grid,

Grid 4 - signal grid,

Grid 5 - screen grid.

Development - 6SA7/1R5 type (converter).

Grid 1 - oscillator grid,

Grid 2 - screen grid,

Grid 3 - signal grid,

Grid 4 - screen grid,

Grid 5 - suppressor grid.

Development - 6L7 (mixer).

Grid 1 - signal grid,

Grid 2 - screen grid,

Grid 3 - oscillator injection grid,

Grid 4 - screen grid,

Grid 5 - suppressor grid.

There is no such thing as a suppressor in Minecraft.

The Maxim suppressor was made of steel.

In general, no. Will depend on the specific holster AND the specific suppressor.

Suppressors (or moderators) may be attacked a number of ways, depending on the design of the suppressor. Some use the same threads which the flash suppressor uses, and require you to remove the flash suppressor first. However, you must also replace the standard crush washer with a peel washer when doing this. Some are designed to work in conjunction with a flash suppressor designed to facilitate the attachment of a sound suppressor.. Advanced Armaments designs come to mind here, with their suppressor-capable versions of the Blackout flash suppressor.