Thanks for your attention!

THIS IS GUERNSEY 1966 10 SHILLINGS, WILLIAM I - NORMAN CONQUEST 900th ANNIVERSARY, UNC 

Composition     Copper-nickel (75% cu, 25% Ni)
Weight     11.31 g
Diameter     25.4 mm
Thickness     2 mm
Shape     Square with rounded corners
Technique     Milled
Orientation     Medal alignment ↑↑
Demonetized     Yes
References     KM# 19

YES WE DO COMBINE POSTAGE