The glass on the standard vent free unit has been replaced with a metal heat shield for added durability

which means you may need a different hitch ball for each trailer you plan to pull

High In Calcium For Strong Plant Tissue Development & Disease Resistance

Plus the actual size of the tank is smaller

Casual Canine Mesh Dog Harness Style:ZA888 16 17 The glass on the standardCasual Canine offers remarkable quality at an unbelievable price in these lightweight, breathable mesh dog harnesses. Fully adjustable for an easy fit Features a quick release plastic buckle, and a nickel plated D ring for leash attachment Available in pastel and bold, bright colors Each includes a hangtag. Coordinating Leads are available. See item ZA006. Material: Polyester mesh Sizing Guide: Measure the broadest part of dogs chest. Size Chest Size