BCB International is a British company manufacturing a huge variety of military and police products. One of their latest products is a rifle stock called FRAMM which was first introduced during the DSEI 2017 arms exhibition. The stock allows shouldering and aiming the rifles with virtually all kind of helmets on including the police ones showed in the top image with the visor fully lowered. It also should fit a wide variety of gas masks.
This stock is also adjustable. The articulated design allows adjusting it to one of 9 positions thus getting the proper geometry most suitable for use with any particular helmet or gas mask. The stock also features a rubber butt pad. The FRAMM stock is compatible with the following firearms: FN SCAR, HK MP-5 A2, Beretta ARX-160, HK MP5K, HK G36, B&T GL06 launcher, Remington ACR, CZ 805 BREN, SIG SG 550/551, HK UMP and B&T APC556.
The stock is made in black color only. It has a 210mm (8 1/4″) length and weighs 400 grams (14 oz). The manufacturer also specifies the “deployed height drop” to be 250mm (about 10″). That probably refers to the lowest position drop.
The FRAMM stock should be most useful for the law enforcement market.
The way they solved the problem of clearing the helmet should be their competitive advantage on the market. Unlike other stocks of similar purpose, FRAMM stock is adjustable and on the lowest drop setting pretty much becomes a conventional stock.