X10 Express -- faulty controllers and no refund

I bought three X-10 appliance modules (automatic controllers to switch appliances on and off) on eBay from this seller. The first one proved to be defective: it switched on at random intervals, making it useless and indeed dangerous to use. I tried a second one with the same result. I then contacted the seller and asked for a refund, and received this promising reply:

Reference number: LTK9203103332X Please use this ticket number in any correspondence with us. I am sorry that you have been inconvenienced.

Dear Customer,

Thank you for contacting us.

Please return the item to:

X10 Express

3709 Hillsdale Dr.

Flower Mound, TX 75022

RMA#LTK9203103332X

Securly pack the items and write the RMA number on the outside and include a copy of this email inside the package.

Please feel free to contact us if you have any additional questions.

Sincerely,

Junea

I packaged them up and mailed them Priority Mail--and nothing happened. I emailed and received the runaround: what was the transaction number? When I provided the transaction number, the individual replied that since so much time elapsed, he or she would refund only $19 of my $39 (plus $8 postage).

Of course the $19 never arrived.

Thieves is what they are. Don't do business with them!