# Bellow Covers For Profile Rail Assemblies

When additional protection is required the use of NOOK bellows is recommended. The chart below indicates the bellows dimensions. PVC coated polyester material is used exclusively. Neoprene-cloth and chemically resistant materials are also available upon request.

 Bellow Model No. Profile Rail Model No. W H h Above or Below Block LL Factor JS15 NH-15 EA 48 24.5 5 Above 6mm 1.28 NH-15 ER 41 23.5 5 Above 6mm 1.28 JS20 NH-20 ER 51 28 5 Above 3mm 1.28 NU-20 ER 46 26.5 4 Above 4mm 1.28 JS25 NH-25 EA 51 28 7 Even 1.28 NU-25 ER 47 28.5 4 Above 1mm 1.28 JS30 NH-30 EA 58 35 7 Even 1.20 NU-30 ER 60 35 7 Even 1.20 JS35 NH-35 EA 72 40 8 Even 1.17 NU-35 ER 70 40 8 Even 1.17 JS45 NH-45 EA 83 45 11 Even 1.17 NU-45 ER 81 47 11 Even 1.17 JS55 NH-55 EA 100 55 14 Even 1.13 NU-55 ER 100 55 12 Even 1.13 JS65 NH-65 EA 117 68 14 Even 1.11

*Add 10mm to bellow compressed length for hardware. See unit conversion.

## LL Factor Calculations

 Maximum Extended Length (Lmax) = Stroke × Nook LL Factor
 Minimum Collapsed Length (Lmin) = Maximum Extended Length - Stroke

### Example:

For a Rail Cover for a Nook-NH65. The Rail Cover is Nook-NH65
Stroke = 10" and LL Factor = 1.11
Convert to metric since most calculations are in metric.
Stroke = 10 x 25.4 = 254.00mm
Maximum extended length = 254 x 1.11 = 281.94mm
Round off to the next full number Lmax - Stroke
Lmin = 282.00 - 254.00 = 28.00mm

### Summary:

For Nook-NH65 Rail Cover using PVC-Poly Material
Stroke = 254.00mm
Lmax = 282.00mm
Lmin = 28.00mm
Figure 1