There is actually only one sex machine on display here: The Thrillhammer. On camera, it looks like a medical bench with a giant gold dome on one end, and it sounds like nothing more than a lawnmower engine. Seven super-cute amateurs choose to impale themselves on the little latex probe that protrudes from that big motor, and the camera's there to catch the sexual roller coaster rides that result.
From that simple premise comes great delight. This is essentially a solo tape with mechanical accoutrements, although Malika and Kitty vary the routine by adding a blowjob to the mix. Both give enthusiastic head, with Malika getting throat-fucked especially well as she bucks and grinds to a climax.
Those looking for a lot of close-ups of girls being penetrated by machines will be disappointed, but that's about the only flaw of this movie. It would seem that seven scenes with the same machine could get repetitive, but these girls are so enthusiastic, then surprised, then turned on, then driven to the throes of ecstasy by the Thrillhammer, that each scene is a turn-on. This tape combines fetishistic mechanical action with the best virtues of the amateur genre.