Thanks varmintshooterYou may not need it but they sure help at times.
Thanks guys all good infoI found them useful for hunting groundhogs in the summer. These days I normally hunt late afternoon to dusk. In some fields, there is just no way around setting up, so the sun is facing you. That's where the sunshield can be useful to help mitigate the glare of the sun off the scope objective lens.
However, I've never found them necessary hunting big game in PA.
PS: If none are available commercially, you can easily make your own. Take 4 sheets of heavy-duty construction paper and form a tube around the objective of your scope. Use Scotch tape to connect the ends when you mold to the proper diameter to fit your scope.
Finish off with duct tape by wrapping the entire length of the tube. This will give it a strong construction and protect against rain. I've found that a 4" extension beyond the objective provides the necessary sun shading. Depending on the design of your scope's objective, make sure you have about 3" of the tube covering the objective end of the scope. It ain't pretty but it works.
A cardboard tube is better if you can find one that fit the objective.