Seems a offer for the TUBE blue at 3,99 USD using coupon : UFHA
but from my account always show expired. I comment here in any case. FLASH SALE is 5,99 USD
According to Fin17, all blue tubes were sold out in short period of time. Last time a tube was for sale for about $4,-, like 2 months ago or so, it was sold out quickly too, resulting in code not working anymore.
The lot for this sale was quite large (of 300 units), I can assume that it has been allowed to buy more than 1 or 2 units per account …. Maybe for this type of offer it would be preferable to limit the number of units Per account.