SMLE Rifle Action Implement
Short Magazine Lee-Enfield Rifle Action Implement, Mk II
Long before combination folding tools became a must-have item in every tool catalog, the British Army was issuing multi-purpose tools for use with Snider muskets, Martini-Henry, Metford and Enfield rifles. The 1904 SMLE combination tool is a marvel of compact simplicity.
The “Implement, action, rifle, short, M.L.E., Mark I” makes its first appearance in the List of Changes (LoC) on 2 February 1904. (LoC 12057). 
"The implement is for use in stripping and re-assembling the stock fore-end and action, and testing the length and radius of the striker point of "Rifles, short, M.L.E.," also for stripping and re-assembling the bolt of "Sword-bayonet, pattern 1903."
Six years later, (LoC 15337, 3 Nov 1910) we see something highly unusual: the same LoC is used to introduce both a new version (Mk II) and to specify changes to those already in the field. The altered tools are identified as Mk I, Altered to Mk II. Although intended for unit armourers, it is likely that this simple and highly versatile tool saw issue to non-commissioned officers as well. It was not intended for issue to the common soldier.
The example we have is a Mk II. We have reproduced the description of the various parts of the tool as it appears in the original LoC's.
"The following is a description of the various parts of the tool, showing the screws, &c., for which they are used.
(a) Driver, screw..For screws - band, inner; cap, nose, back; guard, trigger, front; plate, butt; sight dial, fixing; spring, sight, aperture.
(b) Driver, screw..For screws - bed, back sight, back and front; cut off; extractor; keeper, fine adjustment; handguard, cap; protector sight, top; nut, keeper, striker; and protector, sight, side.
(c) Driver, screw..For screws - band, outer; swivels, piling and butt; cap, nose, front; disc, marking, butt; ejector; guard, back; sear; spring, sight, back; and stop, charger guide.
(d) Driver, screw, forked...For screw, sight, dial, pivot.
(e) Tool, extractor spring, removing and replacing.
(f) Tool, expanding magazine link. (Note: the Mk I and Mk I, Altered will have a cupped recess in the area marked by the white lines.)
(g) Driver, screw, forked...For nut, bolt, sword-bayonet, pattern 1903.
(h) Gauge, striker point, height and figure."
This particular example is highly unusual in that it was made by the "trade" and not RSAF Enfield. The maker's mark (Central with an "O" superimposed on the "T") is unknown to us.
Notes & Sources
 Officially, the full name is of the official document is “List of Changes in British War Material In Relation to Edged Weapons, Firearms and Associated Ammunition and Accoutrements.” .