Dolle INSTA-Rail Vertical Cable Railing Inserts for deck railing- 42"H Easy, affordable deck upgrade with DIY Vertical Cable Inserts from Dolle. Vertical Cable Inserts for replacing wooden deck railing pickets or spindles. INSTA-RAIL vertical cable balusters for 42 code high railings - CHECK CODE COMPLIANCE before ordering. 1 insert kit spans 72" of deck railing. Span between top and bottom rail should 30.5". Assembly Required. Cables spaced 4" on center - may not meet all building codes. Verify code requirements prior to purchase. 304 Stainless Steel - not recommended for direct salt water spray.