Direct Protect 6 month supply dog flea and tick prevention – $31.99 with coupon

Amazon has a $4 coupon on Direct Protect brand flea & tick control. Almost half the price of the Frontline Plus we usually buy and says it contains the same ingredients. Reviews seem decent
5-22lb dogs is $31.99 with coupon:
https://www.amazon.com/dp/B0002DHR2E
23-44lb dogs is $35.28
https://www.amazon.com/dp/B07P2BDSC9
45-88lb dog is $35.53
https://www.amazon.com/dp/B07NY3RT8Y
89-132lb dog is $40.83
https://www.amazon.com/dp/B07P2BF411