When traditional mail marketing has been displaced by and huge with bulk emails the same principles of marketing apply for both forms of direct communications. The objective of all direct marketing is to create a favorable first impression which draws the target into spending time absorbing the information offered which if properly structured offers a series of logical reasons why the offer you are making should be considered. What is interesting is that those companies which also add promotional products to the package they are using to lure people into engaging with their message have a proven effectiveness which is 500% greater than those simple messages which are provided without accompanying merchandise. 
Imagine that your company was giving a new financial investment scheme to an established list of customers. We all know how much clutter fills both electronic and physical letter boxes these days so it is a simple matter for most people to discard anything which they see which is not immediately recognizable or does not hold the hope of providing something relevant or entertaining. When people sight your promotional offering, even something as humble as a pen or a notepad they are far less likely to ignore it or immediately dispose of it and indeed while they may toss out anything which accompanies the gift they will certainly hold onto the gift item inside. 
Simple matters like sending out printed invoices to your clients can also be made more streamlined and effective by making an inexpensive branded promotional item to the mail out. Say for instance you add a small packet of confectionery to the envelope by way of a “thank you” gift to the recipients. People will surely look more favorably upon your financial demands than they will otherwise and even the most difficult situation can be eased with the effective addition of the right piece of branded merchandise. Not only does the simple gift make people feel luckier about the less pleasant aspects of the communication they have received but the right promo item included can ensure that the next time the same service or china promotional products you have provided is required you will be the first person on the list to be offered the opportunity to quote. 
Consider the example of a company which wants to reactivate a stale list of addresses and get people to respond so that the contact list can be updated and used more effectively to generate sales in the future. Say your offer is that people who send back the coupon or reply to your email will receive a custom branded pen which looks like a much more expensive brand. One of the best advantages of promotional merchandise based marketing is that you can leverage the apparent value of an item on offer compared to a much lower actual cost to your company, because people respond better to your marketing activities.