Zenport SSLPG1000 Zen-Tek Liquid Filled Stainless Steel Pressure Gauge, 0-1000 PSI Liquid glycerin filled 0-1000 psi pressure gauge; grade A accuracy of 1.6% full range 2.5-inch diameter ABS case with 372 plastic window; 0.25-inch NPT bottom connection and stainless steel internals withstand high corrosive environments Dampening action of the liquid makes readings possible during conditions of rapid dynamic loading and vibration Better performance in corrosive environments and immunity to moisture penetration and icing Liquid helps to lubricate all moving elements, improving the lifespan of the gauge; high visibility dial face and numbers