From the Support Staff at ShootersProShop.com:

Hello Sir,

They are basically the same bullet. They are both Nosler E-tip bullets, but the 25 cal 101 grain bullet is a OEM bullet that Nosler makes for Federal to load in their ammunition. The only difference other than the weight is that the 101 grain bullet will have a black polymer tip instead of the normal Olive Drab tip color that the normal E-tips have. The reason the 25-101gr E-Tip is on sale is because we have a couple hundred bags. Please let me know if you have any other questions.

Thank you,

Mark

All that is necessary for the triumph of evil is that good men do nothing -- Edmund Burke