Be carerful opening two blades on the same spring half way!
One of the Marbles MR278 Demo Knives I bought came with a no MR number Marbles SPORK. All four blades were opened half or less.
One of the mainsprings was broken before it was released from the hang-pack.
(Marbles/SMKW replaced it under warrantee when I emailed them a photo of the broken spring.)
To help avoid a busted mainspring: Open one blade fully and one halfway on the same spring. (good advice for any 4 blade 2 spring knife without half stops, regardless of brand or age,)
The MR278 is a great knife, isn't it? I like the lack of "CAN OPENER" stamped on that blade. I guess the generals and admirals decided recruits (and NCO's ... Officers ...)
ARE ... "smart enough" to know what that blade is for after all?
The MR278
is a smidgeon smaler than my issued by Army Reserves 1975 Western Demo Knife, which also lacks the match strike pulls. Other than that (and no "CAN OPENER" stamped on that blade on the Marbles) they are identical... and equally as rugged/strong.