Very positive I feel the use of (2) Standard - AAA batteries that you get in any supermarket. No expensive button cells so. The battery compartment closes securely and seems to be a weak point of the device, at least from the first impression.
The processing leaves a somewhat cheap impression. The spring of the "finger clip" is a little too light in relation to the weight of the unit. The wearing comfort, however, is very pleasant. The display is not such, but a low-cost LED display according to the principle of an old clock radio. This may also indicate no O2 saturation of the 100 Pulsoxy, it simply lacks a body. Clear whether 99 or 100 plays in practice no role, but still ... The readability even in the dark (at night) No problem. Positive battery warning indicator should be evaluated.
Measuring is easy: press the Create button and knob. More operating elements, the device also does not exclude a data storage is not possible. A measurement takes 8 seconds, which is not outstanding, but quite practical. The values obtained are compared to an Oxi-Max N560 professional equipment in order. If the device no pulse on it in five seconds in standby mode.
Conclusion: Three stars for the device alone, and a star as a bonus for the price and the accessories package. The CMS-50DL can not replace a professional device, but complement each other very meaningful and also provides a perfect backup and "On the Road." - Represents solution therefore from me a clear recommendation!