The phot r professional 3 axis bubble level camera hotshoe features acrylic construction and fits a standard photo accessory shoe three individual spiritbubble levels are encased in clear acrylic and the unit incorporates a moulded accessory shoe mount the design ensures that at least two of the three levels will read no matter how you orient your camera so you dont have to remove the bubble level and flip it as you may with some other bubble levels each level is filled with bright yellow