Safety is #1 consideration. Versatile, robust in design, heavy duty brass fittings, schedule 80 PVC tubing, enameled 3/4" plywood base components, fits 16+ known plastic bottle sizes, perfect 100% air tight seal, safety feature on trigger prevents accidental firing, all trigger mechanism parts are stainless steel, unique interchangeable launch tubes for different length to fit all bottle sizes and custom rockets, 100 psi safety pressure relief valve (for external air intake), 115 psi safety pressure relief valve (for internal CO2 pressurization), 0-100 psi pressure gauge, quality airtight line check valve, stainless steel/teflon water intake shut off, another stainless steel/teflon valve allows pressure to be bled off to safely abort a launch, wonderful & convenient feature is the ability to hook up directly to garden hose for direct water fill, rocket can also be filled before mounting on launcher, quality long threaded "Schrader" (brand name) air valve stem fits standard tire pumps and compressor hose air chucks and air chucks with lock-on clips, adjustable to launch from vertical to horizontal, handy locking compartment under base holds all accessories with hinge and stainless steel hasp. Carry handle can be used to carry launcher with up to three rockets in one hand! Newly added features are 3 each very solidly mounted brass anchors that attach the conduit (plumbing) to the plywood base. Manifolds and risers located on top of the base, mount to the brass anchors. Also added it a water bled feature that allows you to bled the water out of the mounted rocket to align to a fill line on the rockets (for consistency). Also new is a redesigned 5" riser (all schedule 80 fittings and pipe) and matching brass anchor that has been machined with a groove for a very positive O Ring seal. Many more features not mentioned, but this should give you an idea of the features and quality. LOOK AT SOME NEW PHOTOS (actually new photos need updating to reflect all the new features)