I visited both of your websites, YouTube Channel, and your Facebook sites. If your online marketing is fueling your sales then I think you should continue in that direction.
However it doesn't hurt to diversify a little and test out other offline advertising mediums. Here is what I would suggest.
Based on your online analytics data, you should know which industries are driving your online sales. You can create direct mail postcards with Q.R codes and target those industries. The Q.R codes, when scanned by the users mobile device, can drive them to an online video demonstration of how your shrink wrap products can be used in their business. Then provide a call to action at the end of the video like "Call us now for more information" to get a response.
There is a service called Sendpepper that will allow you to track visitors that come directly from your postcard. Based on the data you will know quickly if sending to a specific industry or demographic using direct mail is a waste of time or if it will be profitable. You can also test things on your flyer like the ad copy, headlines, graphics, etc and know immediately which combination is the most effective to convert customers into buying your products.
You can also use ad tracking numbers to determine what part of the country calls are coming from and direct your marketing efforts in that part of the region.
I think this could be very profitable for you if planned out correctly. One thing I noticed on your site is that you have no lead capture forms. You are losing a lot of money by not being able to send out emails on promotions, specials, etc.
Let me know if you want me to explain further. Hope this gives you some direction.