objectFlange

let properties = {
    10: {
        '10': {
            multiplier: 4,
            boltSize: 14
        },

function calculate(size, pressure, units) {
    return properties[size][pressure] ? properties[size][pressure].multiplier * units : properties[size].multiplier * units;
}

console.log("size = 100, pressure = 6, units = 10, caculated holes --> ", calculate(size, pressure, units) + properties[boltSize]);