stargate prop need help

so i was watching the stargate sg1 season 2 episode 1 and i saw this detonator i really wanna make.. does anyone have any better pics or idea? it looks like a multimeter rubber casing and i dont no what else.. i have a multimeter i will upload pics of that reminds me of this.. well here is a screen shot of the item..

 

Yeah i'm pretty sure that they used a multimeter to build it. Like this one : Digital multimeter Mastech - MAS345

removing the buttons and then place a plastic piece over the other part.

 

i can see the black "casing" being a multimeter but green part.. idk i see the screen but..hmm.. also that red/white card opened a door to show the red button... so i wanna make it functional..