ThinkGrow’s Model-H Plus 4' is a 720 W, eight‑bar LED top light built for high‑PPFD indoor cultivation. The 4‑foot chassis delivers over 2160 μmol/s PPF with four independently controllable spectrum channels (UV, white, deep red, far red) and on‑board dimming; it also integrates with TrolMaster Hydro‑X for group control. Sized for a true 4‑foot canopy width, typical coverage is 4 ft x 4 ft in flower or up to 5 ft x 5 ft in veg. The fixture measures 44.98 x 45.5 x 5.30 in and weighs about 14.36 kg, carries an IP56 rating, and is rated L90 beyond 54,000 hours. Diodes used are Samsung LM301B whites with Samsung LH351H 660 nm deep red on eight plug‑and‑play bars.