Russian masks

The Soviet and later Russian militaries have utilised a number of different gas masks models. These include:
 * IP-4
 * IP-4M
 * IP-5
 * IP-6
 * GP-5
 * GP-6
 * GP-7
 * MM1
 * PDF-D
 * PMG
 * PMK
 * PBF
 * PRWU
 * SCHMS