Astralpool / Hurlcon HX series heaters are some of the most robust spa gas heaters ever made. HX 70, HX 120. Replaces MX 125, MX 150, MiniMax, HiNRG 175 and more.
The Raypak Spartan 131 is in the same category of robustness as the Astral HX gas heaters. It replaces all older Raypak spa heaters, including the Premium 127, 167, etc
Astralpool JX series heaters are a wall-mounted, fan-forced gas heater used for tight spaces, or where you just want the heater up and out of the way. Robust & efficient.