Slide rail and slide rail assembly

1. An innermost slide rail of a slide rail assembly, comprising:

a longitudinal body; and

a pair of longitudinal supporting structures extended from two sides of the longitudinal body, each of the supporting structures having a U-shaped cross section and comprising a first supporting arm and a second supporting arm bent relative to the first supporting arm, wherein the first supporting arm is extended from the longitudinal body, the second supporting arm is reversely bent relative to the first supporting arm and extended toward the longitudinal body, a ball raceway is formed on one of the first supporting arm and the second supporting arm.

2. The innermost slide rail of claim 1 , wherein the ball raceway is formed on the first supporting arm.

3. The innermost slide rail of claim 1 , wherein the ball raceway is formed on the second supporting arm.

4. The innermost slide rail of claim 1 , wherein the first supporting arm has at least one portion contacting the second supporting arm.

5. A slide rail assembly, comprising:

a first rail having a first longitudinal body, and a pair of first arms extended from two sides of the first longitudinal body, a first passage being defined by the pair of first arms and the first longitudinal body, wherein a first ball raceway is formed on each of the first arms and located within the first passage;

a second rail movable within the first passage of the first rail, the second rail having a second longitudinal body, and a pair of second arms extended from two sides of the second longitudinal body, a second passage being defined by the pair of second arms and the second longitudinal body, wherein each of the second arms has a first arm section and a second arm section, a second inner ball raceway is formed on the first arm section, a second outer ball raceway is formed on the second arm section; and

a third rail movable within the second passage of the second rail, the third rail being an innermost rail of the slide rail assembly, the third rail having a third longitudinal body, and a pair of longitudinal supporting structures extended from two sides of the third longitudinal body, each of the supporting structures comprising a first supporting arm extended from the third longitudinal body and a second supporting arm reversely bent relative to the first supporting arm and extended toward the third longitudinal body, wherein a third ball raceway is formed on one of the first supporting arm and the second supporting arm to face toward the second inner ball raceway of the second rail.

6. The slide rail assembly of claim 5 , wherein each of the supporting structures of the third rail has a substantially U-shaped cross section.

7. The slide rail assembly of claim 5 , wherein the third ball raceway is formed on the first supporting arm.

8. The slide rail assembly of claim 5 , wherein the third ball raceway is formed on the second supporting arm.

9. The slide rail assembly of claim 5 , wherein the first supporting arm of the third rail has at least one portion contacting the second supporting arm of the third rail.

10. The slide rail assembly of claim 5 , wherein the third rail further comprises a connection part extendedly connected between the first supporting arm and the second supporting arm.

11. The slide rail assembly of claim 5 , wherein the second arm further has a third arm section extended and bent from the second arm section.

12. The slide rail assembly of claim 11 , wherein the third arm section is extended toward the first arm section.

13. The slide rail assembly of claim 11 , wherein the third arm section has at least one portion contacting the first arm section.