The BB405 5-String Bass Bridge is dual loading, ensuring it will meet the needs of any kind of bass guitar player. Great as a replacement or for a brand bass build, it also features a locking saddle for superior sustain, intonation and sound transfer.
Top Loading
When top loading, the strings are top mounted to the back of the bridge, which means a slightly lesser string tension than that of a through body. This will make the guitar sound more resonant and lively, improving the overall tone of your bass guitar.
String Thru
When using a string thru bass bridge, you'll have increased tension versus that of a top-loading bridge, which some players prefer as it gives you a more stable playing platform, particularly when you're plucking with your fingers. It really comes down to personal preference which you prefer, as both will sound equally great, just different.