The MiniTemp Temperature Logger:

This unique logger is a complete temperature data logger encased in a rugged stainless steel case. It contains a digital thermometer, a calendar clock, a battery, and memory to log temperature samples from 1.4 to 364 days.

It withstands harsh environments of dirt, water, grease, freezing, and rough physical treatment. It can be reused over and over, - with a service life of 3 to 10 years.
Carry, mount, or tether theMiniTemp logger with this plastic fob.
An example of a plastic mounting method. 
        Stainless Steel Clip 
MiniTemp Logger Specifications: 
     
 Physical 
 Diameter: 17.35 mm 
 Thickness: 5.89 mm
 Weight: 3.3 grams
 Hermetic Seal: Rated IP68: 1 meter of water for 1 hr.
 Service Life: Approx. 1,000,000 Temperature Samples
                          or 3 yrs. to 10 yrs.
 Temperature Range: -10C degrees  to +80C degrees  version
                                    -20C degrees to +80C degrees version 
                                    -40C degrees to +80C degrees version 
Accuracy: +/- 1 degree C 
Resolution:  0.5 degrees C
 Clock Accuracy: +/- 2 minutes/month from 
                               0  degrees C to 45 degrees C
 Maximum Number Of Readings Per Mission: 2,048
 Serial Number: 12 Digits, Globally Unique
PHOTOLOGIC LTD. Federal Building, 39 Queen St., Suite 214, Cobourg, Ontario K9A-1M8 Canada
Tel: (905) 377-8915
Each MiniTemp logger has a globally unique serial number programmed inside for positive identification.
Plastic Halo color codes multiple buttons, and accepts handwriten identification.
 Reuse the MiniTemp  logger over and over. Its service life is 
 about 5 years of logging using a 3 minute sample rate.