These vials are made to the highest standards and they have a reliable and repeatable bubble movement and consistent sensitivity. This is due to the high quality moulding, and the cleanliness of the internal surfaces and the liquid, and the tight control over the bubble size and the rest of the manufacturing process. These should not be compared to the cheap lookalike products made in China. These are quality vials for applications that actually need to be set level within a specific degree of accuracy. They are available in a range of sizes and sensitivities that can suit precision levelling, or hand held devices. They have a wide operating temperature range, and are suitable for outdoor use. We can offer advice to OEM’s on product selection, different mounting techniques, and how to get the best bubble contrast and visibility.