Rotary Date Indicator for Mason Jar Lids

PROBLEM
Food in mason jars are left for storage with the contents' expiration dates being forgotten.

SOLUTION
Design a re-usable lid with rotary dial date indicator so that jar contents' expiration will no longer be forgotten.

This rotary date indicator fits between the lid and ring hence the original jar lid is used providing better seal and 3d-printed part is touching the jar contents.

DIRECTIONS

Print files as oriented using no supports. Use a small dab of glue to attach the dials to the knobs.

To use, put the assembled rotary date indicator in-between the jar lid and ring. Turn the wider knob to select the month of the year, smaller knob for the day of the month.  

A numeric/combination-type version is also available.