To avoid coming up short when cutting to length.
1. Measure the outside door height dimension and subtract 39mm. Measure outside door width dimension and subtract 39mm . Do not try inserting seal and then marking it to cut.
2. Use a cutting mat. Put down a piece of thin double sided tape along top front edge of cutting mat. Measure out and mark cut lines. I used a piece of blue painters tape.
3. Start with a longer side first. Roll out the seal on top of the double side tape(longest edge of seal to tape.). Try not to stretch it. Cut at your marked cut line at 90 degrees.
4. Test fit cut piece. It should fit edge to edge. Too short, it can used for the short side. Adjust cut mark if needed. repeat for the other 3 lengths.
5. I mitered the top and bottom seals only. fit a side seal and use it as a guide to mark the angles- I used a gel pen to mark the black rubber. Repeat with top seal placing on bottom edge. Cut top and bottom miters on cutting mat using a sharp knife.
6. Install both side seals. Bottom seal and top seal. You should have tight mitered corners.
