What is the difference between the one available on the kel-tec website and the one on the bersa website. Kel-tec's is $6.65 and the Bersa one is $5.00. I was also wondering if I get the bersa one (part 48 on their site) do I also need part 47 (magazine bottom holder) for another $1.00? Obviously, the price isn't a big deal for a matter of dollars. I just wanted to know the difference between the two, if any, and what I actually need if I go with the bersa. I'm aware of the +1 extension from kel-tec, just don't see it as necessary now.