The PayPayPlast RZ-115 / RHA-503ATC is an optical car refractometer that checks antifreeze, screenwash and battery electrolyte with one instrument. Its scales cover 0 to -50 °C for G11/G12 and G13 antifreeze, 0 to -40 °C for screenwash, and 1.10–1.40 kg/L for electrolyte. ATC compensates for air temperatures from +10 to +30 °C.

Specifications

What you get

• One instrument, three fluids — antifreeze, screenwash and battery electrolyte.
• Separate G11/G12 and G13 scales — both from 0 to -50 °C in 5 °C steps.
• Battery health by density — 1.10–1.40 kg/L in 0.01 kg/L steps.
• Winter-ready screenwash — frost resistance from 0 to -40 °C.
• Readings without corrections — ATC adjusts them at air temperatures from +10 to +30 °C.
• Small sample — just 2–3 drops, pipette included.
• Fits the glovebox — the body is 170 mm long.

Who it is for

DIY car owners who want to check all three fluids with one tool, auto electricians assessing batteries, and garage mechanics ahead of seasonal fluid changes.

Who it is not for

Anyone who needs to measure sugar content, salinity or other liquids outside the automotive scales: this instrument is built for antifreeze, screenwash and electrolyte. Also anyone who wants readings on a screen rather than in an eyepiece.

Use and compatibility

Freezing point of ethylene glycol (G11/G12) and propylene glycol (G13) antifreeze, frost resistance of screenwash, electrolyte density to judge battery charge and condition, and general control of car technical fluids. No compatibility with specific fluid brands is claimed.

What is in the box

Refractometer, pipette, calibration screwdriver, manual, plus a case or soft cloth depending on the kit.

Questions and answers

Why are there separate G11/G12 and G13 scales?

Ethylene glycol (G11/G12) and propylene glycol (G13) antifreeze bend light differently, so each has its own scale; both show the freezing point from 0 to -50 °C.

Can I test screenwash outside in freezing weather?

ATC works at air temperatures from +10 to +30 °C, so bring the fluid and the instrument into a warm room first. The screenwash scale runs from 0 to -40 °C.

How often should I calibrate it?

Before a series of readings, or whenever distilled water does not read 0 °C (WATERLINE). Use the screwdriver from the set.

What comes in the set?

Refractometer, pipette, calibration screwdriver and manual, plus a case or soft cloth depending on the kit.

How compact is it?

The body is 170 mm long, so the refractometer fits in a glovebox or toolbox.