Cialis 20mg with 120 pills can be purchased at many pharmacies, both brick-and-mortar and online. It is important to purchase medications, including Cialis, from a reputable source to ensure that you are getting a safe and effective product.

Here are some options for buying Cialis 20mg with 120 pills:

1. Local pharmacy: You can visit a local pharmacy and purchase Cialis 20mg with 120 pills over the counter or with a prescription from your doctor.
   
2. Online pharmacy: You can also purchase Cialis 20mg with 120 pills from an online pharmacy. Be sure to choose a reputable online pharmacy and make sure that the website is secure before entering any personal or payment information.
   
3. Direct from the manufacturer: Some pharmaceutical companies offer the option to purchase medication directly from them.

It's important to note that purchasing medication from an unreliable source could result in receiving a counterfeit or unsafe product. Before purchasing Cialis 20mg with 120 pills, make sure to research the seller and ensure that they are a reputable and trustworthy source.