Below is a conversation with a seller on ebay for a helmet purchase and its defects- just an fyi

Original message to Ivy2 helmets

We purchased a modular helmet from you in December 2011, this week during a ride the visor was down and the entire side of the visor attachment including the visor blew off. I need to know if this is replaceable.

Thank you

From Ivy2

Hello. We are very sorry to hear that the visor is defective. Do you
know the model of the helmet that you ordered?? 936 Modular Flip Up? We do apologize for the inconvenience. Thank you and hope to hear from you
soon!

Of course I sent them the model # in response I get:

Thanks so much for your response. Unfortunately we have discontinued the old Modular Dual Visor helmets that we used to have in stock. We have just released all new models for the Spring as far as Dual Visor helmets. We really do apologize for any inconvenience. Thanks again!

I responded getting a little upset with:

Even though this model had been discontinued I have only had this
helment for 6 mths and riding time had only been for 3 mths you are not gonna try to fix your defect? I am not sure I understand why your brushing customer service to the side?

They reply:

We are not brushing customer service to the side at all we would hate for you to think that. We never sold replacement visors for the model 806 or 822 Dual Visor helmets for there is the inner smoked visor that retracts down out of the helmet. As far as clear visors, we do not sell replacement clear visors for any of our helmets. We really do apologize for this matter, as well as discontinuing this model. If you would like to make a purchase on the website for something you may use the 15% coupon code:
SEASONSALES15. We hope that this makes up for our shortcomings. Thank you for all of your time!

My response:

Actually your offer for 15% off is a nice gesture although with the
amount of time I have owned this helmet I did expect more and therefore will no longer order from you company. I will also post this information on our MC clubs website and I will send a message and a copy of the messages we have had to the DOT concerning the defect and the damage it could of caused by blowing off into the traffic behind me. I understand you have discontinued the helmet but this does not help those that are already owned.

Ivy 2 Said:

We really are very sorry to hear that you are so unsatisfied with your
purchase and our company. All of our helmets are DOT approved and do meet the safety requirements (FMVSS218). We rarely ever hear from customers regarding this matter and safety matters, so we do apologize that this happened. What exactly happened to the visor?? It snapped off while you were riding?? Thank you again for all of your time.

I gave the details:

The helmet was being worn. I was riding about 60 miles Per hour on the interstate. The visor was closed it blew off. The entire side connector snapped off. I was on a ride with a group of other riders this visor flew behind me causing other riders to swerve.

They determined:

Wow! Well we definitely will be sure to take note of this and contact our Manufacturer even though we do not make this specific model anymore. You should be able to ride with the clear visor up and open up to about 25 mph but if it is closed there should be no problem. We really are very sorry and apologies go to you and your other riders involved in this incident.

My advice:

I advise you to go to a reputable dealer one that will stand behind and replace their merchandise.