Official abbreviation: H.T.H.
Instituted September 26th 1945 by King Christian 10th.
The oak leaf device was instituted 8. November 2005 by Queen Margrethe II.
Awarded to personnel in the Danish Army for 25 years of service, after their 20th birthday.
After 40 years of service, a Gold Oak-leaf will be added to the ribbon.
Design: Worn in a red ribbon with a wide white centre stripe. The obverse shows the monogram of King Christian X.
Other information: Personnel eligible for the Fortjenstmedalje, will get that instead of the 40 years Long Service Medal.
Official decree (Danish)