Today I’m running the rule over four terrific small caps.

Bolting ahead

Thanks to the ubiquity of its products, I reckon Trifast (LSE: TRI) is a great stock for those seeking reliable earnings growth year after year.

The bolt-and-fastening maker’s products can be found in a wide array of applications, from domestic appliances and home electronics right through to cars.

Indeed, the latter segment accounts for a third of group revenues. And with global auto sales surging steadily higher — and Trifast steadily increasing the amount of product ‘loadings’ per unit — I expect profits to continue pounding higher.

This view is shared by the City, and Trifast is expected to record earnings expansion of 6% in both of the years to March 2017 and 2018. I reckon that consequent P/E ratings of 13.5 times and 12.7 times make the manufacturer great value.

Lighting it up

Like Trifast, a healthy car market should underpin sterling results at Carclo (LSE: CAR).

The West Yorkshire business provides lighting units for automobiles, and its Wipac division — which provides product for supercars such as Aston Martin — is performing particularly strongly at present.

But cars aren’t the be-all-and-end-all for Carclo, with the company also providing lighting across a variety of other applications, not to mention plastic products for the medical and electronics industry. And the business has opened new facilities and expanded existing bases across North America, Asia and Europe during the past year to meet future demand.

The number crunchers expect earnings to keep rattling higher at Carclo, the firm is anticipated to enjoy earnings growth of 21% in the periods to March 2017 and 2018. The manufacturer deals on subsequently-cheap P/E ratios of 13 times and 10.8 times for these years.

In the fast lane

It’s impossible not to come across Hill & Smith’s (LSE: HILS) products during the course of the day.

The company manufactures an array of road-related furniture, and the company’s broad range of hi-tech barriers in particular makes it the go-to manufacturer for roadbuilders across the globe. This quality makes Hill & Smith a strong beneficiary of the ‘UK Road Investment Strategy’ to improve transport infrastructure up and down the country.

With Hill & Smith’s other industrial products also flying off the shelves, the City has pencilled-in earnings growth of 7% for 2016 and 12% for 2017. Consequently, a P/E rating of 16.5 times for the current period slips to an attractive 15.2 times for next year.

A defence delight

Defence play Avon Rubber (LSE: AVON) lit up the leaderboards in Wednesday trading following the release of blockbuster results, the firm last 11% higher on the day.

Avon Rubber announced that both revenues and pre-tax profits advanced 5% during October-March, helped by solid mask demand from the US Department of Defense. Indeed, the company received a further 167,000 orders for its M50 model during the period, giving the company what it describes as “a strong forward order book.”

The mask builder is also enjoying a growing pipeline from non-DOD clients in the Americas and the Middle East. And elsewhere, the firm’s Milkrite milk-extraction system is also performing well despite difficulties in the dairy industry.

The City expects earnings at Avon Rubber to dip 5% in the period to September 2017, although an 8% rebound is anticipated for next year. I reckon consequent P/E ratios of 13.7 times and 12.8 times represent great value given the manufacturer’s exceptional revenues outlook.

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Royston Wild has no position in any shares mentioned. The Motley Fool UK has no position in any of the shares mentioned. We Fools don't all hold the same opinions, but we all believe that considering a diverse range of insights makes us better investors.