Prime-Line B 521 Roller Assembly, 1 in Dia Roller, 1/4 in W center groove nylon wheel, high-tension 2-1/2 in L heat-treated steel spring and #8 x 3/8 in Phillips pan head sheet metal screw.
| Material | : | Plastic/Steel |
| Type | : | Door Rollers |
| Finish | : | Unfinished |
| Number of Rollers | : | 2 |
| Dimensions | : | 2-1/2 in L |
| Roller Diameter | : | 1 in |
| Roller Width | : | 1/4 in |
| Suitable for | : | Roll Formed Screen Doors and Sliding Screen Doors |
| Includes | : | (2) #8 x 3/8 in Phillips Pan Head Sheet Metal Screws |
| Bearing Type | : | Ball |
| Roller Edge Type | : | Concave |
| Spring Type | : | Straight |