This mech paper model is Mektek Grizzly, a BattleMech that was developed by Clan Ghost Bear scientists in the 30th century, from the video game MechWarrior 4, the papercraft is created by Shiftdel, and the scale is in 1:40. The size of finishedmodel is about 263 (H) x 166 (W) x 146 (D) mm.
Unfortunately, the design excels at no one thing, so it never carved a niche in the Clan's touman. Thirteen tons of armor are mounted on an Endo Steel frame. Jump jets are mounted so that the Grizzly can leap up to 120 meters at a time. Aside from the jack-of-all-trades, master-of-none moniker, the Grizzly is also poorly engineered. Slagged armor tends to get stuck in joints and weapons, while the actuators are difficult to repair in their own right. Production ceased in 3013 and the remaining 'Mechs were relegated to green Provisional Garrison Clusters. [Source: sarna]
You can download the papercraft model here: MechWarrior 4 - Mektek Grizzly Free Mech Paper Model Download [Joint Set]