The Lo-Pro Edge is a redesign of the original Edge tremolo which gives it a lower profile (hence the name). On the original Edge the string lock screws pass under the fine-tuners, while on the Lo-Pro Edge, the string locks and fine tuners are independent of one another. This design allows the Lo-Pro protrude less from the top of the body, minimizing interference with the player's picking hand and arm.
Like the original Edge, the Lo-Pro Edge is based on the Floyd Rose tremolo design which Ibanez & Gotoh licensed. In this design the strings are clamped at both the bridge and nut which effectively minimizes the length of the strings which contributes to increased tuning stability.
Also like its predecessor, the Lo-Pro Edge's body is cast from dense metal to increase mass which helps to increase sustain. It also retains the other key improvements introduced by the Edge including locking anchor studs mounted in steel sleeves, replaceable knife edges, and a convenient pop-in arm.
When introduced in 1991, the Lo-Pro Edge was fitted on the higher-end tremolo equipped guitars, such as Steve Vai's JEM models. The RG5xx, RG7xx, JS, and FGM models continued to use the original Edge. In 1992, it became the standard tremolo for all high-end models. Starting in 1997 select high-end RG models reverted back to the original Edge.
A seven string Lo-Pro Edge 7 variant was introduced concurrently with the six string model.
For 2003, both the original Edge and the Lo-Pro Edge were replaced by the completely new Edge Pro, which has a low profile design reminiscent of the Lo-Pro Edge. After 2003, the Lo-Pro continued only in the K7 signature model due to the unique U-bar. An Edge Pro Model fitted with a U-bar replaced the Lo-Pro Edge in the K7 for 2007.
For 2010, the Lo-Pro Edge and original Edge were reintroduced on a few models. Both tremolos continue to be offered on a variety of high end models.