MKIV GSR with Type E MkV. The date of the filter, September 1939, is interesting as I didn't think they were making MkV filters this early. Some info in comments. : r/gasmasks
Meiwa oil filter for Suzuki GSR 750 2011-2016
PS-1004 K&N Pro Series Oil Filter for Mitsubishi Cordia GSR AA, AB, AC Turbo 2.0 | eBay
MWR Suzuki GSR 750 (2011-12) Air Filter – APX RACING USA
GSR Training Filters For Gas Mask Respirator | #1777922150
BMC FM449/04 SUZUKI GSR 600 GSR600 SPORTS AIR FILTER YEAR 2007 2008 2009 8032872867711 | eBay
Scott GSR Gas Mask Filter Set
British Army GSR Gas Mask Filters NEW
New Filters for GSR Gas Mask by British Army
British Army GSR Respirator & Filters Military Gas Mask - Size 3 [JH07 – Pools Surplus Stores
GSR (general service respirator) spare canister filter British Army - Walk This Way
K&N Typhoon Air Intake Kit | 2008-2015 Mitsubishi Evo X GSR (69-6546TW – MAPerformance
FM12 with Scott GSR filter via adapter : r/gasmasks