VEVOR Window Door Awning Canopy, 38" x 117" Door Canopy Exterior, UF50+ PC Sunshade Sheet Awnings, Outdoor Patio Awning Sun Shade, Transparent, Waterproof, for Sun Shutter, UV, Rain, Snow Protection

Yes, panels can be added to go beyond the 120".

Dear Customer, Thanks for your inquiry. Kindly note that yes you can. Thanks for choosing vevor.

While product information mentions it is easy to install, customers disagree. Reviews suggest it is difficult to install alone.

I did not find any information about spare parts availability from the product description or customer reviews.

The product description states it offers UPF 50+ sun protection, shielding from harmful UV rays. Customers generally agree with one reviewing that it looks great but does not provide adequate UV protection.