Give a google search and find out dude, take the information you get and do a bit of research.
Gives you answers quicker and saves people like me for doing that work for you

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Its a UTG M234, no doubt about it. It looks like an APS-2 but UTG made their own little internal system which is kinda fucked up. Like I said, its proprietary stuff. UTG has released their own little upgrade kits for them but i'm unsure if they cover sears. Maybe, maybe not.