U Packer 3mm Blue (50/Bag)

Blue U Packers for the precise positioning of window and door frames. They can be easily slid around existing fixings without removing screws, helping to maintain accurate datum and line during set-out.Each packer is colour-coded for quick on-site identification. The rigid, non-compressible polymer provides a stable bearing under typical frame loads, while the internal comb design ensures a secure grip that resists movement during tightening and final fixing.The material is non-absorbent and non-staining, ensuring a clean, professional installation against both frames and substrates. These U shaped shims provide moderate packing capacity for alignment where small but noticeable correction is needed. Used singly for general alignment or combined with finer sizes to tune level precisely, they maintain consistent plane across the bearing face to protect frame profiles and finishes.The 3mm thickness is suitable for establishing reveals and squareness with fewer pieces.