Weapons File from Battle Action Force No. 598, dated 18 October 1986. The SA80 or Enfield Endeavour as it is called here. Introduced in the British Armed Forces in 1985, but upgraded by Heckler & Koch in the 2000's, it's probably more commonly referred to as the L85 family of guns with the most recent variant being the L85 A3.
It replaced the SLR (Self-Loading Rifle), otherwise known as the L1A1, the FAL (if you're a Call of Duty player) or "that gun with the wooden bits you got with Action Man".
The Light Support Weapon, the L86, shown above had also been given the commercial name of the Enfield Engager.
The L86 family are a "bullpup" design where the trigger grip is located in front of the breech and magazine instead of behind them, reducing the overall length of the gun. In the case of the SA80, and some other bullpups, this made firing them left-handed (or with a dominant left eye) 'difficult' as the ejection port is next to the face and the bullet cases exited to the right. This could result in quite a mouthful. Some bullpups are ambidextrous so not sure why the L85 was set up like this other than tradition. The FAMAS, for example, was the first bullpup in military service in the 1970's but could be converted to either left or right handed use.
The L85 is going to be replaced soon. I don't think a final decision has been made however some parts of the UK Armed Forces are going to be issued with the non-bullpup Knight's Stoner 1 (KS-1, below).