The behemoth really is an impressive piece of rifle - a REALLY beefy bullpup, quite unlike the more timid / intimidated P15 / P35 rifles, this beefy boy has all the good stuff loaded into it, all of which are externally adjustable;

This rifle has an overpressure relief valve, likewise fitted w/ a burst disc that will expire before any critical pressure damage can occur to your air reservoirs. We think these are two good safety backstops, necessary as well, for a 300 BAR PCP gun.

Regulator (From 100 BAR ~ 200 BAR of pressure.) - You can only adjust UP when the rifle is filled up. If you try to adjust downward, you'll likely damage the regulator and/or seals attached to it) The higher your regulator pressure, the higher your consistent muzzle velocity, but the higher your air consumption / the lower your amount of regulated shots 

Externally adjustable hammer spring - This is accomplished by means of an M3 allen wrench. Rotating the screw head at the back, under the rifle action, inward, increases muzzle velocity. Rotating it the other way, decreases muzzle velocity. Just note that the manufacturer indicates that, possibly after about 500 shots, the hammer spring will break in and you will lose 50 FPS. 

Easy accessable bleeder screw - Just chuck an allen wrench in and you can bleed out the entire air reservoir. Comes in handy if you nneed to tune your regulator pressure up or would just like to disassemble your rifle for repairs (maintenance) / modifications / inspection.

Integrated filling probe - Just thread off the end cap on the nose-end of the air reservoir, as shown in the gallery lineup, then you can refill your air rifle. No need to keep a filling probe lying around / losing it. 

Vertically adjustable buttplate - The buttplate can be adjusted tool-free up and down to suit your ergonomy, merely by pulling it out, positioning it where it would suit your shooting stance best, then releasing it into the closest locking position. 

Integrated sling swivel points - If you have a two point sling w/ sling swivels, then you can attach these directly onto your rifle, w/ no modifications needed and carry your rifle as such when perhaps, going through the bush / hunting expedition. 

Side cocking lever - Nothing beats simplicity of chambering, and the BEHEMOTH offers this. No laggy feel on the lever when hinging it out, no overt stiff feeling as you max out its arc of motion. 

Integrated stock slots for 2x spare multishot magazines - This is some more tacticool added to the rifle, which speeds up reload times, keeping your magazines out of your pockets, where your keys and wallet could otherwise hinder you from quickly withdrawing a consecutive magazine. These magazines feature an 8 shot capacity, which, in no time at all, will deplete. Best to have your spares close at hand.

Dedicated hybrid Picatinny / Dovetail rail - This is nifty, as you can now use a single-piece mount ring base to affix your scope to your rifle. Moreover, you have the freedom to chuck it anywhere on the rail, w/out needing to mind your pellet magazine / breech slot. The rifle features a guage on each side of the receiver - The one that has the green markings up to 300 BAR is your fill guage, the one that has green markings up to 200 BAR, would be your regulator guage. Please don't try to push your regulator pressure beyond 200 BAR and also familiarize yourself in full with the instruction manual prior to changing any settings on the rifle. At your request, we can preset your rifle for you as per your preference, even zero it in for you as well, to be able to put pellet onto an A4 sheet @ 50m's (on condition you purchase an optical sighting device in conjunction w/ this rifle)