This item does exactly what it says on the tin! I bought one, delivered next day with amazon prime, and within 5 minutes it was up and running. No Techy knowledge required, literally just plug it in the line between your coax aerial feed and the TV, locate the "eye" somewhere that it can see your remote control, and so long as you have turned on the RF power on your sky+ box, bingo, you're in business. (Turning on the RF power is from the menu on the sky+ box. Search on google and instructions are available)
Great simple design, that works perfectly, no batteries, no hassle, no problem! I can't recommend this highly enough.